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Delaware		1311		86-0460233
(State or other jurisdiction of incorporation or organization)		(Primary Standard Industrial Classification Code Number)		(I.R.S. Employer Identification No.)

Kelly B. Rose Baker Botts L.L.P. 910 Louisiana One Shell Plaza Houston, Texas 77002 (713) 229-1234		Cyrus D. Marter IV Forest Oil Corporation 707 Seventeenth Street Suite 3600 Denver, CO 80202 (303) 812-1400		Alan P. Baden Shelley A. Barber Vinson & Elkins L.L.P. 666 Fifth Avenue, 26th Floor New York, NY 10103-0040 (212) 237-0000

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	Sincerely yours,
	/s/ Scott D. Josey
	Scott D. Josey
	Chairman, Chief Executive Officer and President

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	Sincerely,
	/s/ H. Craig Clark
	H. Craig Clark
	President and Chief Executive Officer

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	•	to consider and vote upon the adoption of the Agreement and Plan of Merger, dated as of September 9, 2005, among Forest Oil Corporation, Forest Energy Resources, Inc., Mariner Energy, Inc. and MEI Sub, Inc., subject to the approval of the amendment to Mariner’s certificate of incorporation described below,
	•	to consider and vote upon a proposed amendment to Mariner’s Second Amended and Restated Certificate of Incorporation to increase the number of authorized shares of stock from 90 million to 200 million, subject to the completion of the merger,
	•	to consider and vote upon the proposed amendment and restatement of the Mariner Energy, Inc. Stock Incentive Plan,
	•	to elect one director to serve until the annual meeting of stockholders in 2009,
	•	to elect two directors to serve until the annual meeting of stockholders in 2007,
	•	to grant to the proxyholders the authority to vote in their discretion with respect to the approval of any proposal to postpone or adjourn the annual meeting to a later date to solicit additional proxies in favor of the other proposals, if there are not sufficient votes for approval of the other proposals at the annual meeting, and
	•	to transact any other business that may properly come before the annual meeting.

	By Order of the Board of Directors
	of Mariner Energy, Inc.
	/s/ Teresa Bushman
	Teresa Bushman
	Vice President and General Counsel

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QUESTIONS AND ANSWERS ABOUT THE MERGER				1
SUMMARY				8
	The Companies			8
	Conditions to the Completion of the Merger			11
	Termination of the Merger Agreement			12
	Termination Fee and Expenses			12
	Certificate of Incorporation and By-Laws			13
	Financing Arrangements Relating to the Spin-Off and the Merger			13
	Ancillary Agreements			13
	Regulatory Matters			13
SUMMARY SELECTED HISTORICAL AND PRO FORMA FINANCIAL DATA				14
	Sources of Information			14
	How We Prepared the Unaudited Pro Forma Combined Condensed Financial Information			14
	Summary Historical Consolidated Financial Data of Mariner			15
	Summary Selected Consolidated Statements of Revenues and Direct Operating Expenses of the Forest Gulf of Mexico Operations			18
	Summary Selected Unaudited Pro Forma Combined Condensed Financial Information			20
	Comparative Per Share Data			21
	Comparative Stock Price and Dividends			22
RISK FACTORS				23
	Risks Related to the Spin-Off and the Merger			23
	Risks Related to the Combined Operations After the Merger			25
	Risks Related to our Common Stock After the Merger			33
CAUTIONARY STATEMENT CONCERNING FORWARD-LOOKING STATEMENTS				35
THE MARINER ANNUAL MEETING				36
	Purpose, Time and Place			36
	Recommendation of the Mariner Board of Directors			36
	Record Date; Stock Entitled to Vote; Quorum			36
	Votes Required			37
	Voting by Proxy			37
	Interests of Certain Persons in the Merger			38
	Stock Ownership of Directors and Executive Officers			39
	Appraisal and Dissenters’ Rights			39
THE SPIN-OFF AND MERGER				40
	Background of the Merger			40
	Reasons for the Merger; Recommendation of the Mariner Board of Directors			47
	Certain Financial Projections			49
	Opinion of Mariner’s Financial Advisor			51
	The Spin-Off			60
	Stock Exchange Listing			61
	Certificate of Incorporation and By-Laws			61
	Material United States Federal Tax Consequences of the Spin-Off and the Merger			61

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	Federal Securities Laws Consequences of the Merger			68
	Accounting Treatment			69
	Regulatory Matters			69
	Appraisal and Dissenters’ Rights			69
STRENGTHS AND STRATEGIES OF MARINER FOLLOWING THE MERGER				70
THE MERGER AGREEMENT				73
	The Merger			73
	Representations and Warranties			74
	Covenants			76
	Additional Covenants			81
	Conditions to the Completion of the Merger			82
	Termination of the Merger Agreement			84
	Amendments and Waiver			86
THE DISTRIBUTION AGREEMENT				87
	Summary of the Transactions			87
	Contribution of the Forest Gulf of Mexico Assets and Assumption of Liabilities			87
	Spin-off			88
	Representations and Warranties			88
	Indemnification			88
	Conditions to the Spin-off			89
ANCILLARY AGREEMENTS				90
	Tax Sharing Agreement			90
	Employee Benefits Agreement			91
	Transition Services Agreement			92
FINANCING ARRANGEMENTS RELATING TO THE SPIN-OFF AND THE MERGER				93
UNAUDITED PRO FORMA COMBINED CONDENSED FINANCIAL INFORMATION				95
SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA FOR MARINER				103
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS OF MARINER				106
	Overview			106
	Critical Accounting Policies and Estimates			111
	Results of Operations			114
	Liquidity and Capital Resources			119
	Contractual Commitments			125
	Off-Balance Sheet Arrangements			126
	Recent Accounting Pronouncements			126
	Quantitative and Qualitative Disclosures About Market Risk			127
MARINER				128
	Significant Properties			129
	Estimated Proved Reserves			132
	Production			134
	Productive Wells			134
	Acreage			135
	Drilling Activity			135
	Property Dispositions			136

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	Marketing and Customers			136
	Title to Properties			136
	Competition			136
	Royalty Relief			137
	Regulation			138
	Employees			141
	Legal Proceedings			141
	Insurance Matters			141
	Enron Related Matters			142
SELECTED CONSOLIDATED STATEMENTS OF REVENUES AND DIRECT OPERATING EXPENSES OF THE FOREST GULF OF MEXICO OPERATIONS				143
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS OF THE FOREST GULF OF MEXICO OPERATIONS				144
THE FOREST GULF OF MEXICO OPERATIONS				149
FOREST OIL CORPORATION				157
MANAGEMENT OF MARINER				158
	Directors and Executive Officers			158
	Board of Directors			160
	Committees of the Board			161
	Compensation Committee Interlocks and Insider Participation			161
	Director Compensation			161
	Indemnification			161
	Executive Compensation			162
	Employment Agreements and Other Arrangements			163
	Overriding Royalty Arrangements			163
	Equity Participation Plan			164
PROPOSAL TO AMEND AND RESTATE MARINER STOCK INCENTIVE PLAN				167
MARINER SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT				174
DESCRIPTION OF MARINER CAPITAL STOCK				175
	Common Stock			175
	Liability and Indemnification of Officers and Directors			175
	Preferred Stock			175
	Anti-Takeover Effects of Provisions of Delaware Law, Our Certificate of Incorporation and Bylaws			176
	Transfer Agent and Registrar			178
COMPARISON OF STOCKHOLDER RIGHTS				179
EXPERTS				182
LEGAL MATTERS				182
SUBMISSION OF FUTURE STOCKHOLDER PROPOSALS				182
GLOSSARY OF OIL AND NATURAL GAS TERMS				183
WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE				185
ANNEX A
	Agreement of Plan and Merger			A-1
ANNEX B
	Lehman Brothers Inc. Fairness Opinion to the Mariner Board of Directors			B-1

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ANNEX C
	Distribution Agreement			C-1
ANNEX D
	Tax Sharing Agreement			D-1
ANNEX E
	Proposed Amendment to Second Amended and Restated Certificate of Incorporation of Mariner Energy, Inc.			E-1
ANNEX F
	Report of Ryder Scott Company, L.P., Independent Petroleum Engineers			F-1
ANNEX G
	Mariner Energy, Inc. Amended and Restated Stock Incentive Plan			G-1
Opinion of Baker Botts L.L.P.
Form of Opinion of Baker Botts L.L.P.
Form of Opinion of Weil, Gotshal & Manges LLP
Form of Nonstatutory Stock Option Agreement
Consent of Deloitte & Touche LLP
Consent of KPMG LLP
Consent of Ryder Scott Company, L.P.
Consent of DeGolyer and MacNaughton
Form of Proxy Card of Mariner Energy, Inc.

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	•	a proxy statement of Mariner for use in the solicitation of proxies for Mariner’s annual meeting of stockholders;
	•	a prospectus of Mariner relating to the issuance of shares of Mariner common stock in connection with the merger; and
	•	an information statement of Forest relating to the spin-off of the Forest Gulf of Mexico operations to the shareholders of Forest.

	•	The terms “we”, “us”, “our” and like terms, and the term “Mariner,” refer to Mariner Energy, Inc.;
	•	“MEI Sub” refers to MEI Sub, Inc.;
	•	“Forest” refers to Forest Oil Corporation;
	•	“Forest Energy Resources” refers to Forest Energy Resources, Inc.; and
	•	“Forest Gulf of Mexico operations” refers to the offshore Gulf of Mexico operations conducted by Forest that have been contributed to Forest Energy Resources and the shares of which will be spun-off to Forest shareholders.

Q:		Please briefly describe the proposed merger and related transactions.
A:		Forest has transferred and contributed the assets and certain liabilities associated with its offshore Gulf of Mexico operations to Forest Energy Resources, a newly formed subsidiary of Forest. Immediately prior to the merger, Forest will distribute all of the outstanding shares of Forest Energy Resources to Forest shareholders on a pro rata basis. Forest Energy Resources will then merge with a newly formed subsidiary of Mariner, and become a new wholly owned subsidiary of Mariner. When the merger is complete, approximately 58% of the Mariner common stock will be held by shareholders of Forest and approximately 42% of Mariner common stock will be held by the pre-merger stockholders of Mariner, each on a pro forma basis.

	•	be an independent public company;
	•	own both the Mariner operations and the Forest Gulf of Mexico operations; and
	•	have total assets of approximately $2.1 billion and total debt of approximately $279.0 million on a pro forma combined basis, assuming the spin-off and the merger occurred on September 30, 2005.

Q:		What are Mariner stockholders being asked to vote upon?
A:		Mariner stockholders are being asked to

		• adopt the merger agreement entered into among Forest, Forest Energy Resources, Mariner and MEI Sub, Inc., subject to the approval of the proposed amendment to Mariner’s certificate of incorporation;

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		• approve the proposed amendment to Mariner’s certificate of incorporation to increase the number of authorized shares of stock from 90 million to 200 million, subject to completion of the merger;
		• approve the proposed amendment and restatement of Mariner’s stock incentive plan;
		• to elect one director to serve until the annual meeting of stockholders of Mariner in 2009;
		• to elect two directors to serve until the annual meeting of stockholders of Mariner in 2007; and
		• approve the proposed granting of authority to the proxyholders to vote in their discretion on a motion to adjourn or postpone the meeting.

Q:		What changes to Mariner’s stock incentive plan am I being asked to approve?
A:		You are being asked to approve an amendment and restatement of the plan whereby 4.5 million shares of common stock would be added to the plan, the plan would be extended to October 12, 2015 and the number of shares subject to stock options or shares of restricted stock issuable under the plan to any individual would be limited to 2.85 million, subject to the completion of the merger.
Q:		Why am I being asked to grant to the proxy holders the authority to vote in their discretion on a motion to adjourn or postpone the meeting?
A:		We may determine to adjourn or postpone the meeting, for example, to solicit additional proxies if there are insufficient votes at the time of the meeting to adopt the merger agreement.
Q:		What will Forest shareholders receive in the merger?
A:		If the merger is completed, each Forest shareholder will ultimately receive shares of Mariner common stock. As a result of the spin-off, Forest shareholders will initially receive shares of Forest Energy Resources, which will then be converted in the merger into the right to receive shares of Mariner. After the merger, Forest shareholders will be entitled to receive approximately 0.8 shares of Mariner for each Forest share that they own. Forest shareholders will not be required to pay for the shares of Forest Energy Resources distributed in the spin-off transaction or the shares of Mariner issued in the merger. Shareholders who would hold less than one full Mariner share after the merger will receive cash in lieu of such fractional share. All shares of Forest Energy Resources common stock distributed in the spin-off and Mariner common stock issued in the merger will be issued in book-entry form, meaning that, although Forest shareholders will own the shares, they will not be issued physical share certificates.
Q:		What will Mariner stockholders receive in the merger?
A:		Mariner stockholders will keep the shares of Mariner common stock they currently own, but will not receive any additional shares in the merger.
Q:		Does the Mariner board of directors support the merger and the other proposals?
A:		Yes. The Mariner board of directors has determined that the merger is fair to and in the best interests of Mariner and its stockholders, and that the merger agreement is advisable. The Mariner board of directors has unanimously approved the merger agreement and the other proposals and recommends that the Mariner stockholders vote “for” the adoption of the merger agreement and the other proposals. A more detailed description of the background and reasons for the merger is set forth under “The Spin-Off and Merger” beginning on page 40.
Q:		Do the directors and executive officers of Mariner have interests in the merger that are different from mine?
A:		When considering the recommendations of the Mariner board of directors, you should be aware that the directors and executive officers of Mariner have interests and arrangements that may be different from your interests as stockholders, including:

	•	arrangements regarding the appointment of directors and officers of Mariner following the merger; and
	•	arrangements whereby the executive officers of Mariner will receive a cash payment of $1,000 each in exchange for the waiver of certain rights under their employment agreements, including the automatic

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		vesting or acceleration of restricted stock and options upon the completion of the merger and the right to receive a lump sum cash payment if the officer voluntarily terminates employment without good reason within nine months following the completion of the merger.

Q:		What factors did the Mariner board of directors consider in reaching its decision on the merger?
A:		In reaching its decision on the merger, the Mariner board of directors considered a number of factors, including the following among others:

	•	the increased size of the combined company could reduce volatility and allow it to participate in larger scale drilling projects and acquisition opportunities;
	•	the merger would be expected to increase Mariner’s estimated proved reserves and undeveloped acreage;
	•	the merger could generate increased visibility in the capital markets and trading liquidity for the combined company;
	•	the merger would increase the number of Mariner’s producing fields, thereby reducing Mariner’s dependence on a concentrated number of properties;
	•	the merger would be consummated only if approved by the holders of a majority of the Mariner common stock; and
	•	the merger is structured as a tax-free reorganization for U.S. federal income tax purposes and, accordingly, would not be taxable either to Mariner or its stockholders.

		The Mariner board of directors also identified and considered some risks and potential disadvantages associated with the merger, including, among others, the following:

	•	the risk that there may be difficulties in combining the business of Mariner and the Forest Gulf of Mexico operations;
	•	the risk that the potential benefits sought in the merger might not be fully realized;
	•	the risk that the proved undeveloped, probable and possible reserves of the Forest Gulf of Mexico operations may never be converted to proved developed reserves; and
	•	the fact that, in order to preserve the tax-free treatment of the spin-off, Mariner would be required to abide by restrictions that could reduce its ability to engage in certain business transactions.

		In the judgment of the Mariner board of directors, the potential benefits of the merger outweigh the risks and the potential disadvantages.
Q:		Did Mariner’s financial advisor render its opinion with respect to the fairness from a financial point of view of the exchange ratio in the merger?
A:		Yes. Lehman Brothers Inc., Mariner’s financial advisor, has delivered to Mariner’s board of directors a written opinion that, as of September 9, 2005, based upon and subject to the factors and assumptions set forth in the opinion, the exchange ratio in the merger was fair from a financial point of view to Mariner. This opinion is attached as Annex B to this proxy statement/ prospectus-information statement.
Q:		Are there risks that Mariner stockholders should consider in deciding whether to vote on the merger?
A:		Yes. Mariner stockholders should read the “Risk Factors” beginning on page 23 for a description of various risks Mariner stockholders should carefully consider in evaluating the proposed merger.

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Q:		Can Mariner stockholders dissent and require appraisal of their shares of Mariner common stock?
A:		No. Mariner stockholders are not entitled to dissenters’ rights or appraisal rights in connection with the merger.
Q:		Why does Mariner want to increase the number of authorized Mariner shares?
A:		Mariner’s certificate of incorporation currently does not authorize a sufficient number of shares of common stock to complete the merger. Mariner currently is authorized to issue 70 million shares of Mariner common stock and 20 million shares of Mariner preferred stock. As of December 21, 2005, approximately 35.6 million shares of Mariner common stock were issued and outstanding. Under the terms of the merger agreement, Mariner must issue approximately 50.6 million shares (representing approximately 0.8 shares of Mariner common stock for each share of Forest common stock) of common stock in the merger, which would result in approximately 86  million shares of Mariner common stock outstanding. Therefore, the number of authorized shares of Mariner common stock must be increased in order to complete the merger.
Q:		What vote is required to adopt the merger agreement and the other proposals?
A:		For the merger to occur, the holders of a majority of the outstanding Mariner common stock must adopt the merger agreement and approve the amendment to the certificate of incorporation. The amendment to Mariner’s stock incentive plan must be approved by a majority of votes cast by stockholders present in person or by proxy, a quorum being present. Director nominees receiving a plurality of all votes cast at the meeting will be elected to Mariner’s board of directors. Mariner stockholders will have one vote for each share of Mariner common stock they own. On                     , 2006, the record date for Mariner’s annual meeting,                      shares of Mariner common stock were issued and outstanding and entitled to vote at the meeting. The approval of Forest shareholders is not required for the spin-off or the merger.
Q:		Where will Mariner’s common stock be listed?
A:		We have applied to list Mariner’s common stock on the New York Stock Exchange.
Q:		Who will be the executive officers of Mariner?
A:		The current executive officers of Mariner will remain in their current positions following the merger.
Q:		Who will be the directors of Mariner?
A:		If the merger is completed, Mariner’s board will consist of seven members, five of whom will be the current directors of Mariner, and two of whom will be mutually agreed between Mariner and Forest prior to the completion of the merger. The Chairman of the Mariner board will be Mr. Scott D. Josey, the current Chairman, Chief Executive Officer and President of Mariner.
Q:		Who are the new directors of Mariner, as mutually agreed by Forest and Mariner?
A:		The two Mariner directors to be mutually agreed by Forest and Mariner pursuant to the terms of the merger agreement have not yet been designated. We will update this proxy statement/prospectus-information statement when information with respect to the new directors becomes available.
Q:		When do you expect to complete the spin-off and the merger?
A:		If the merger agreement and the proposed amendment to the certificate of incorporation are adopted and approved by the stockholders of Mariner, then Mariner, Forest, Forest Energy Resources and MEI Sub expect to complete the spin-off and the merger as soon as possible after the satisfaction (or waiver, where permissible) of the other conditions to the spin-off and the merger. We currently anticipate that the merger will be completed during the first calendar quarter of 2006.
Q:		Who is entitled to vote at the meeting of Mariner stockholders?
A:		Holders of Mariner common stock of record at the close of business on                     , 2006.
Q:		What should Mariner stockholders do now?
A:		You should mail your signed and dated proxy card(s) in the enclosed envelope or vote via telephone or via the Internet by following the instructions on your proxy card(s) as soon as possible so that your shares of

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		Mariner common stock will be represented and voted at the meeting. The telephone voting number is                     , and the web address for Internet voting is                     .
Q:		Do Mariner stockholders need to send in their share certificate(s)?
A:		No. Mariner stockholders should not send in their share certificate(s). Mariner stockholders will not exchange their share certificates in connection with the merger; only shareholders of Forest will do so.
Q:		If I am not going to attend the meeting, should I return my proxy card(s)?
A:		Yes. Returning your proxy card(s) ensures that your shares of Mariner common stock will be represented at the meeting, even if you are unable to or do not attend.
Q:		How do I vote my shares of Mariner common stock if they are held in the name of a bank, broker or other fiduciary?
A:		Your bank, broker or other fiduciary will vote your shares of Mariner common stock with respect to the merger only if you provide written instructions to them on how to vote, so it is important that you provide them with instructions. If you do not provide them with instructions, they will not be authorized to vote with respect to the merger or the other proposals. If you wish to vote in person at the meeting and hold your shares of Mariner common stock in the name of a bank, broker or other fiduciary, you must contact your bank, broker or other fiduciary and request a legal proxy. You must bring this legal proxy to the meeting in order to vote in person. Shares of Mariner common stock held by a broker, bank or other fiduciary that are not voted because the customer has not provided instructions to the broker, bank or other fiduciary (referred to as a “broker non-vote”) will have the same effect as a vote “against” the proposals.
Q:		Can I change my vote after I mail my proxy card(s)?
A:		Yes. If you are a record holder of Mariner common stock, you can change your vote by:

		• completing, signing and dating a new proxy card and returning it by mail to our proxy solicitor so that it is received prior to the meeting;
		• voting via telephone (                    ) or via the Internet (                    ) by following the instructions provided on your proxy card;
		• sending a written notice to the Corporate Secretary of Mariner that is received prior to the meeting stating that you revoke your proxy; or
		• attending the meeting and voting in person or by legal proxy, if appropriate.
		Internet and telephone voters must use the same procedure to revoke or change their votes as they used to cast their original votes. If your shares of Mariner common stock are held in the name of a bank, broker or other fiduciary and you have directed such person(s) to vote your shares of Mariner common stock, you should instruct such person(s) to change your vote or obtain a legal proxy to do so yourself. You may revoke your proxy all the way up until the time of the meeting.

Q:		What if I do not vote, or abstain from voting, or do not instruct my broker to vote my shares of Mariner common stock?
A:		If you do not vote, it will have the same effect as a vote against the merger and the proposal to amend Mariner’s certificate of incorporation. Shares that are not voted will not count for purposes of calculating a quorum, which is necessary to have a valid meeting of stockholders. If a quorum of stockholders is not present in person or by proxy at the meeting, no vote will be taken on the merger and the other proposals. Shares that are not voted have the effect of reducing the number of shares required to approve the proposal to amend and restate Mariner’s stock incentive plan and to elect directors, which require the affirmative vote of a majority of a quorum, but do not have the effect of reducing the number of shares required to adopt the merger agreement and to approve the proposed amendment to Mariner’s certificate of incorporation, both of which require the affirmative vote of a majority of Mariner’s outstanding shares. Abstentions and broker non-votes also will have the effect of votes against the merger and the proposal to

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		amend Mariner’s certificate of incorporation. If you sign your proxy card but do not indicate how you want to vote, your shares of Mariner common stock will be voted for the merger and the other proposals.
Q:		What factors did the Forest board of directors consider in reaching its decision on the spin-off and merger?
A:		In reaching its decision on the spin-off and the merger, the Forest board of directors considered a number of factors, including the following among others:

		• the transaction creates two highly focused and valuable enterprises for Forest’s shareholders, Forest and Mariner;
		• the merger of the Forest Gulf of Mexico operations with the Mariner business creates a high quality, well positioned Gulf of Mexico independent with an excellent track record and growth outlook;
		• following the spin-off, Forest will be a highly-focused onshore resource company with an acquire and exploit strategy and a portfolio of long-life, concentrated assets in high quality basins that provide a foundation for sustainable growth;
		• the determination to execute a tax-free transaction designed to increase the value of Forest’s Gulf of Mexico assets; and
		• the determination that a spin-off followed by a merger transaction represents a better alternative for Forest’s shareholders than any other type of transaction considered, providing optionality and returning value directly to Forest’s shareholders.
		The Forest board of directors also considered some risks and potential disadvantages associated with the spin-off and merger, including the following among others:
		• the lack of a liquid trading market and established market value for the Mariner shares;
		• the risk that there may be difficulties in combining the business of Mariner and the Forest Gulf of Mexico operations;
		• the risk that the potential benefits sought in the merger might not be fully realized; and
		• the risk that the proved undeveloped, probable and possible reserves of the Mariner business may never be converted to proved developed reserves.
		In the judgment of the Forest board of directors, the potential benefits of the merger outweigh the risks and the potential disadvantages.

Q:		Do Forest shareholders need to send in any share certificates?
A:		No. If the merger is completed, Forest shareholders will exchange their shares of Forest Energy Resources for share certificates representing Mariner common stock. Forest shareholders who are entitled to receive shares of Forest Energy Resources (i.e., shareholders of record on the record date for the distribution) will be mailed book entry statements evidencing their shares of Forest Energy Resources. The exchange of Forest Energy Resources and Mariner shares will be effected through book-entry, without the exchange of physical share certificates.
Q:		Has Forest set a record date for the distribution of Forest Energy Resources shares in the spin-off?
A:		No. Forest will publicly announce the record date when it has been determined.
Q:		Can Forest shareholders dissent and require appraisal of their shares of Forest Energy Resources common stock?
A:		No. Forest shareholders are not entitled to dissenters’ rights or appraisal rights in respect of the Forest Energy Resources stock they receive in the merger.

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Q:		What should Forest shareholders do now?
A:		Forest shareholders should carefully read this proxy statement/ prospectus-information statement, which contains important information about the spin-off, the merger, Mariner, the Forest Gulf of Mexico operations and the combined businesses. Forest shareholders are not required to take any action to approve the spin-off or the merger. As described above, if the merger is completed, shares of Forest Energy Resources will be converted into shares of Mariner common stock.
Q:		Who can answer my questions?
A:		If Mariner stockholders have any questions regarding the meeting or need assistance in voting their shares of Mariner common stock, please contact our proxy solicitor:

		All other questions from Mariner stockholders should be directed to:
		Mariner Energy, Inc. Attention: Investor Relations 2101 CityWest Blvd. Building 4, Suite 900 Houston, Texas 77042 Facsimile: (713) 954-5555 Telephone: (713) 954-5500
		All other questions from Forest shareholders should be directed to:
		Forest Oil Corporation Attention: Investor Relations 707 17th Street, Suite 3600 Denver, Colorado 80202 Facsimile: (303) 812-1510 Telephone: (303) 812-1400

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	The market value of our common stock could decline if large amounts of our common stock are sold following the spin-off and merger.

	The integration of the Forest Gulf of Mexico operations following the merger will be difficult, and will divert our management’s attention away from our normal operations.

	•	the challenge of integrating the Forest Gulf of Mexico operations while carrying on the ongoing operations of our business;
	•	the challenge of managing a significantly larger company, with more than twice the PV10 of Mariner on a stand-alone basis;
	•	faulty assumptions underlying our expectations;
	•	the difficulty associated with coordinating geographically separate organizations;
	•	the challenge of integrating the business cultures of the two companies;
	•	attracting and retaining personnel associated with the Forest Gulf of Mexico operations following the merger; and
	•	the challenge and cost of integrating the information technology systems of the two companies.

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	If we fail to realize the anticipated benefits of the merger, stockholders may receive lower returns than they expect.

	We expect to incur significant charges relating to the integration plan that could materially and adversely affect our period-to-period results of operations following the merger.

	The number of shares Forest shareholders will receive in the merger is not subject to adjustment based on the value of the Mariner or the Forest Gulf of Mexico operations. Accordingly, because this value may fluctuate, the market value of the Mariner common stock that Forest shareholders receive in the merger may not reflect the value of the individual companies at the time of the merger.

	Regulatory agencies may delay or impose conditions on approval of the spin-off and the merger, which may diminish the anticipated benefits of the merger.

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	In order to preserve the tax-free treatment of the spin-off, we will be required to abide by potentially significant restrictions which could limit our ability to undertake certain corporate actions (such as the issuance of our common shares or the undertaking of a change in control) that otherwise could be advantageous.

	Some of our directors and executive officers have interests that are different from, or in addition to, the interests of our stockholders.

	•	arrangements regarding the appointment of directors and officers of Mariner following the merger; and
	•	arrangements whereby our executive officers will receive a cash payment of $1,000 each in exchange for the waiver of certain rights under their employment agreements, including the automatic vesting or acceleration of restricted stock and options upon the completion of the merger and the right to receive a lump sum cash payment if the officer voluntarily terminates employment without good reason within nine months following the completion of the merger.

	Oil and natural gas prices are volatile, and a decline in oil and natural gas prices would reduce our revenues, profitability and cash flow and impede our growth.

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	•	domestic and foreign supply of oil and natural gas;
	•	price and quantity of foreign imports;
	•	actions of the Organization of Petroleum Exporting Countries and other state-controlled oil companies relating to oil price and production controls;
	•	level of consumer product demand;
	•	domestic and foreign governmental regulations;
	•	political conditions in or affecting other oil-producing and natural gas-producing countries, including the current conflicts in the Middle East and conditions in South America and Russia;
	•	weather conditions;
	•	technological advances affecting oil and natural gas consumption;
	•	overall U.S. and global economic conditions; and
	•	price and availability of alternative fuels.

	Reserve estimates depend on many assumptions that may turn out to be inaccurate. Any material inaccuracies in these reserve estimates or underlying assumptions will affect materially the quantities and present value of our reserves and the reserves of the Forest Gulf of Mexico operations, which may lower our bank borrowing base and reduce our access to capital.

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	In estimating future net revenues from proved reserves, we and Forest assume that future prices and costs are fixed and apply a fixed discount factor. If these assumptions or discount factor are materially inaccurate, our revenues, profitability and cash flow could be materially less than our estimates.

	Unless we replace our oil and natural gas reserves, our reserves and production will decline.

	Relatively short production periods or reserve life for Gulf of Mexico properties subjects us to higher reserve replacement needs and may impair our ability to replace production during periods of low oil and natural gas prices.

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	Any production problems related to our Gulf of Mexico properties could reduce our revenue, profitability and cash flow materially.

	Our exploration and development activities may not be commercially successful.

	•	unexpected drilling conditions;
	•	pressure or irregularities in formations;
	•	equipment failures or accidents;
	•	adverse weather conditions, including hurricanes, which are common in the Gulf of Mexico during certain times of the year;
	•	compliance with governmental regulations;
	•	unavailability or high cost of drilling rigs, equipment or labor;
	•	reductions in oil and natural gas prices; and
	•	limitations in the market for oil and natural gas.

	Our exploratory drilling projects are based in part on seismic data, which is costly and cannot ensure the commercial success of the project.

	Oil and gas drilling and production involve many business and operating risks, any one of which could reduce our levels of production, cause substantial losses or prevent us from realizing profits.

	•	fires;
	•	explosions;
	•	blow-outs and surface cratering;

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	•	uncontrollable flows of underground natural gas, oil and formation water;
	•	natural disasters;
	•	pipe or cement failures;
	•	casing collapses;
	•	lost or damaged oilfield drilling and service tools;
	•	abnormally pressured formations; and
	•	environmental hazards, such as natural gas leaks, oil spills, pipeline ruptures and discharges of toxic gases.

	Our offshore operations involve special risks that could increase our cost of operations and adversely affect our ability to produce oil and gas.

	Our hedging transactions may not protect us adequately from fluctuations in oil and natural gas prices and may limit future potential gains from increases in commodity prices or result in losses.

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	We will require additional capital to fund our future activities. If we fail to obtain additional capital, we may not be able to implement fully our business plan, which could lead to a decline in reserves.

	Properties we acquire (including the Forest Gulf of Mexico properties) may not produce as projected, and we may be unable to determine reserve potential, identify liabilities associated with the properties or obtain protection from sellers against such liabilities.

	Market conditions or transportation impediments may hinder our access to oil and natural gas markets or delay our production.

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	The unavailability or high cost of drilling rigs, equipment, supplies or personnel could affect adversely our ability to execute on a timely basis our exploration and development plans within budget, which could have a material adverse effect on our financial condition and results of operations.

	Competition in the oil and natural gas industry is intense, and many of our competitors have resources that are greater than ours giving them an advantage in evaluating and obtaining properties and prospects.

	Financial difficulties encountered by our farm-out partners or third-party operators could affect the exploration and development of our prospects adversely.

	We cannot control the drilling and development activities on properties we do not operate, and therefore we may not be in a position to control the timing of development efforts, the associated costs or the rate of production of the reserves.

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	Compliance with environmental and other government regulations could be costly and could affect production negatively.

	Our insurance may not protect us against our business and operating risks.

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	An active market for our common stock may not develop and the market price for shares of our common stock may be highly volatile and could be subject to wide fluctuations after this offering.

	•	actual or anticipated downward revisions in our reserve estimates;
	•	our operating results being less than anticipated;
	•	reductions in oil and gas prices;
	•	publication of unfavorable research reports about us or the exploration and production industry;
	•	increases in market interest rates which may increase our cost of capital;
	•	the enactment of more stringent laws or regulations applicable to our business, or unfavorable court rulings or enforcement or legal actions;
	•	increases in royalties or taxes payable in the operation of our business;
	•	a general decline in market valuations of similar companies;
	•	adverse market reaction to any increased indebtedness we incur in the future;
	•	departures of key management personnel;
	•	increases to our asset retirement obligations;
	•	adverse actions taken by our stockholders;
	•	negative speculation in the press or investment community; and
	•	adverse general market and economic conditions.

	We do not anticipate paying any dividends on our common stock in the foreseeable future.

	Mariner stockholders will experience substantial and immediate dilution as a result of the merger, and may experience dilution of their ownership interests due to the future issuance of additional shares of our common stock, which could have an adverse effect on our stock price.

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	Provisions in our organizational documents and under Delaware law could delay or prevent a change in control of our company, which could adversely affect the price of our common stock.

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	•	the volatility of oil and natural gas prices;
	•	discovery, estimation, development and replacement of oil and natural gas reserves;
	•	cash flow, liquidity and financial position;
	•	business strategy;
	•	amount, nature and timing of capital expenditures, including future development costs;
	•	availability and terms of capital;
	•	timing and amount of future production of oil and natural gas;
	•	availability of drilling and production equipment;
	•	operating costs and other expenses;
	•	prospect development and property acquisitions;
	•	marketing of oil and natural gas;
	•	competition in the oil and natural gas industry;
	•	the impact of weather and the occurrence of natural disasters such as fires, floods and other catastrophic events and natural disasters;
	•	governmental regulation of the oil and natural gas industry;
	•	developments in oil-producing and natural gas-producing countries;
	•	the contemplated transactions, including strategic plans, expectations and objectives for future operations, the completion of those transactions, and the realization of expected benefits from the transactions; and
	•	disruption from the merger making it more difficult to manage Mariner’s business.

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	•	to consider and vote upon the adoption of the Agreement and Plan of Merger, dated as of September 9, 2005, among Forest, Forest Energy Resources, Mariner and MEI Sub, subject to the approval of the proposed amendment to Mariner’s certificate of incorporation,
	•	to consider and vote upon a proposed amendment to Mariner’s Second Amended and Restated Certificate of Incorporation to increase the number of authorized shares of stock from 90 million shares to 200 million shares, subject to the completion of the merger,
	•	to consider and vote upon the proposed amendment and restatement of the Mariner stock incentive plan,
	•	to elect one director to serve until the annual meeting of stockholders of Mariner in 2009,
	•	to elect two directors to serve until the annual meeting of stockholders of Mariner in 2007,
	•	to approve the proposed granting of authority to the proxyholders to vote in their discretion on a motion to adjourn or postpone the meeting, and
	•	to transact any other business that may properly come before the meeting.

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	Submitting Proxies

	•	attending the meeting and voting their stock in person at the meeting,
	•	completing the enclosed proxy card, signing and dating it and mailing it in the enclosed postage pre-paid envelope, or
	•	voting via telephone (                    ) or via the Internet (                    ) by following the instructions provided on the enclosed proxy card.

	Revoking Proxies

	•	completing, signing and dating a new proxy card and returning it by mail to the proxy solicitor so that it is received prior to the meeting;
	•	voting via telephone (                    ) or via the Internet (                    ) by following the instructions provided on your proxy card;

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	•	sending a written notice to the Secretary of Mariner that is received prior to the meeting stating that you revoke your proxy; or
	•	attending the meeting and voting in person or by legal proxy, if appropriate.

	Mariner Energy, Inc.
	Attention: Secretary
	2101 CityWest Blvd.
	Building 4, Suite 900
	Houston, Texas 77042
	Facsimile: (713) 954-5555

	Other Business; Adjournments

	Proxy Solicitation

	Governance Structure. Under the terms of the merger agreement, the board of directors of Mariner after completion of the merger will be comprised of seven individuals, five of whom are current directors

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	of Mariner, and two of whom will be mutually agreed to by Mariner and Forest prior to the completion of the merger.
	Payments for Waivers of Rights under Employment Agreements. The executive officers of Mariner will receive cash payments of $1,000 each in exchange for the waiver of certain rights under their employment agreements, including the automatic vesting or acceleration of restricted stock and options upon the completion of the merger and the right to receive a lump sum cash payment, equal to 2.0 (2.5 for Mr. Polasek and 2.99 for Mr. Josey) times the sum of the officer’s base salary and three year average annual bonus, if the officer voluntarily terminates employment without good reason within nine months following the completion of the merger.
	Severance Arrangements. The executive officers have employment agreements that will remain in effect after the completion of the merger. These agreements generally entitle the officers to severance benefits in the event of a resignation for good reason, a termination without cause or, in the case of Scott Josey’s agreement, Mariner’s non-renewal of the agreement. These severance benefits are comprised of (i) a payment equal to 18 months of salary continuation (two years for Mr. Josey and Mr. Polasek) at the highest rate in effect prior to termination, (ii) health care coverage for a period of eighteen months (two years for Mr. Josey and Mr. Polasek), (iii) an amount equal to the sum of all bonuses paid to the officer in the year prior to the year in which termination occurs, (iv) 100% vesting of all restricted shares under our Equity Participation Plan, and (v) 50% vesting of all other rights under any other equity plans, including our Stock Incentive Plan.
	The employment agreements also provide for certain change of control benefits. Upon termination for any reason other than cause at any time within nine months after a change of control that occurs while the executive is employed, or upon the occurrence of a change of control within nine months following resignation of employment for good reason or termination without cause, the agreements provide for the following benefits: (i) a lump sum payment equal to 2.0 (2.5 for Mr. Polasek and 2.99 for Mr. Josey) times the sum of the officer’s base salary and three year average annual bonus, and (ii) 100% vesting of all rights under any equity plans, including our Equity Participation Plan and our Stock Incentive Plan. The officers are entitled to a full tax gross-up payment if the aggregate payments and benefits to be provided constitute a “parachute payment” subject to a Federal excise tax. Pursuant to the waivers described above, the executive officers will waive their rights to the automatic vesting or acceleration of restricted stock and options upon completion of the merger and to receive a lump sum payment if they terminate their employment with Mariner without good reason within nine months following the completion of the merger.

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	•	the increased size of the combined company, which would have approximately three times the pro forma daily net production of Mariner on a stand-alone basis, could reduce volatility related to large-scale deepwater projects, and could allow it to participate in larger scale exploratory and development drilling projects and acquisition opportunities than would be available to Mariner on a stand-alone basis;
	•	the merger would be expected to increase Mariner’s estimated proved reserves, on a pro forma basis as of December 31, 2004, by approximately 243%, making Mariner larger on a reserve basis than many of its peer companies, and would more than double Mariner’s undeveloped acreage;
	•	the integration of the businesses and the realization of expected benefits could be facilitated by the fact that Mariner is already active in the Gulf of Mexico with assets that are complementary to the Forest Gulf of Mexico assets;
	•	the merger could generate increased visibility in the capital markets and trading liquidity for the combined company, which could enhance the market valuation of Mariner common stock;
	•	the merger would increase the number of Mariner’s producing fields by approximately 400%, thereby diversifying Mariner’s asset base and reducing Mariner’s dependence on a concentrated number of properties;
	•	the assets comprising the Forest Gulf of Mexico operations, which historically have been used as a cash flow generator for Forest, could be candidates for increased exploitation;
	•	oil and natural gas prices are currently at or near historical highs, which could increase the revenues and enhance the profitability of the Forest Gulf of Mexico operations;
	•	the merger would be consummated only if approved by the holders of a majority of the Mariner common stock;
	•	the merger is structured as a tax-free reorganization for U.S. federal income tax purposes and, accordingly, would not be taxable either to Mariner or its stockholders;
	•	the board’s belief that the potential financial benefits stemming from the enhanced growth prospects of the combined company outweigh the anticipated direct and indirect costs of the merger;
	•	the terms of the merger agreement permit Mariner to terminate the merger agreement at any time before the meeting to accept a superior proposal, subject to its obligation to comply with certain procedural requirements and to pay a termination fee and expense reimbursement; and
	•	the opinion, dated September 9, 2005, of Lehman Brothers Inc. to the Mariner board of directors that, as of that date, based upon and subject to the factors and assumptions set forth in the opinion, the exchange ratio in the merger was fair from a financial point of view to Mariner.

	•	the risk that there may be difficulties in combining the business of Mariner and the Forest Gulf of Mexico operations;
	•	the risk that the potential benefits sought in the merger might not be fully realized;

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	•	the risk that the proved undeveloped, probable and possible reserves of the Forest Gulf of Mexico operations may never be converted to proved developed reserves;
	•	the risks inherent in owning properties located in the Gulf of Mexico, including the risks of future hurricanes that could damage or destroy the acquired properties;
	•	the risk that current high commodity prices could fall, thereby reducing the profitability of the acquired operations;
	•	the risk that the merger might not be completed;
	•	the fact that, in order to preserve the tax-free treatment of the spin-off, Mariner would be required to abide by restrictions that could reduce its ability to engage in certain business transactions that otherwise might be advantageous;
	•	the fact that under the merger agreement, Mariner could be required to pay Forest a termination fee and expense reimbursement in certain circumstances; and
	•	certain of the other matters described under “Risk Factors” beginning on page 23.

		2005				2006
Revenue (in millions)		$	230.2			$	421.4
EBITDA (in millions)		$	185.2			$	353.9
Net income (in millions)		$	60.9			$	158.7
Net income per common share		$	1.71			$	4.45
Capital expenditures (in millions)		$	257.4			$	250.5

	•	weighted average common shares outstanding of 35.6 million in both periods;
	•	NYMEX prices for oil and Henry Hub prices for gas, as adjusted for pricing differentials and hedging contracts in place at such date as follows:

		2005				2006
Oil (per Bbl)		$	41.27			$	48.83
Gas (per Mcf)		$	6.86			$	7.87
Total (per Mcfe)		$	6.87			$	7.94

	•	annual production as follows:

		2005				2006
Oil (MBbls)			1.9				2.4
Gas (Bcf)			21.6				38.8
Total (Bcfe)			33.2				53.1

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	•	a depreciation, depletion and amortization rate of $1.84 per Mcfe for 2005 and $1.80 per Mcfe for 2006;
	•	an effective income tax rate of 35% in each period; and
	•	various assumptions relating to delays in scheduled commencement of production at Pluto, Swordfish, Ochre and Dice, suspension of production at producing fields and increased capital expenditures due to Hurricane Katrina.

		2005				2006
Revenue (in millions)		$	214.1			$	529.4
EBITDA (in millions)		$	173.5			$	450.5
Net income (in millions)		$	43.9			$	124.3
Net income per common share		$	0.87			$	2.45
Capital expenditures (in millions)		$	123.0			$	202.3

	•	weighted average common shares outstanding of 50.6 million in each period;
	•	NYMEX prices for oil and Henry Hub prices for gas, as adjusted for pricing differentials and hedging contracts in place at such date as follows:

		2005				2006
Oil (per Bbl)		$	47.42			$	48.41
Gas (per Mcf)		$	6.64			$	7.13
Total (per Mcfe)		$	7.02			$	7.35

	•	annual production as follows:

		2005				2006
Oil (MBbls)			1.5				2.9
Gas (Bcf)			21.3				54.7
Total (Bcfe)			30.5				72.0

	•	a depreciation, depletion and amortization rate of $3.26 per Mcfe for 2005 and $3.43 per Mcfe for 2006;
	•	an effective income tax rate of 35% in each period;
	•	the allocation from July 1, 2005 to December 31, 2005 of general and administrative expenses as set forth in the distribution agreement;
	•	net hedging losses of $11.7 million in 2005 and $19.5 million in 2006;
	•	various assumptions relating to general and administrative expenses to reflect the allocation set forth in the distribution agreement; and
	•	transaction-related expenses of $12 million in 2005.

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	•	the fact that Mariner’s board of directors unanimously approved the merger, including all directors with no interest in the merger other than their interests as stockholders of Mariner;
	•	the fact that the stockholders of Mariner will be given the opportunity to vote on the merger, and that the merger agreement would not be adopted without the affirmative vote of at least a majority of Mariner’s common stock;
	•	the fact that Mariner does not have a controlling stockholder, and that directors and officers of Mariner own less than 11% of the outstanding stock of Mariner;
	•	the fact that independent financial and legal advisors were retained to assist in the negotiation of the terms of the merger agreement, the distribution agreement and the other ancillary agreements; and

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	•	the fact that Mariner received a written opinion from its independent financial advisor as to the fairness, from a financial point of view, of the merger consideration.

	•	the merger agreement, the distribution agreement, the other transaction agreements and the specific terms of the merger;
	•	publicly available information concerning Mariner that Lehman Brothers believed to be relevant to its analysis, including, without limitation, the Amendment No. 1 to the Registration Statement on Form S-1 filed on July 26, 2005 by Mariner;
	•	publicly available information concerning Forest that Lehman Brothers believed to be relevant to its analysis, including, without limitation, the Annual Report on Form 10-K for the year ended December 31, 2004 and the Quarterly Reports on Form 10-Q for the periods ended March 31, 2005 and June 30, 2005;
	•	financial and operating information with respect to the business, operations and prospects of Mariner as furnished to Lehman Brothers by Mariner, including financial projections and oil and gas reserve estimates as of June 30, 2005 for Mariner as prepared by the management of Mariner;
	•	financial and operating information with respect to the Forest Gulf of Mexico operations as furnished to Lehman Brothers by Forest, including financial projections and oil and gas reserve estimates as of June 30, 2005 for the Forest Gulf of Mexico operations as prepared by the management of Forest;
	•	a comparison of the historical financial results and present financial condition of Mariner and the Forest Gulf of Mexico operations with each other and with those of other companies that Lehman Brothers deemed relevant;
	•	a comparison of the financial terms of the merger with the financial terms of certain other transactions that Lehman Brothers deemed relevant;
	•	commodity prices assumptions used by the management of Mariner, commodity prices assumptions published by Lehman Brothers equity research, and commodity prices as quoted on the NYMEX on August 19, 2005 (collectively the “Commodity Price Assumptions”);
	•	estimates of certain proved reserves generated by third-party reserve engineers as of December 31, 2004 for Mariner and the Forest Gulf of Mexico operations;
	•	the potential pro forma impact of the merger on the current financial condition and future financial performance of Mariner, including the impact on Mariner’s operating metrics, including, the composition of its reserves between oil and gas; the percentage of reserves attributable to onshore, the shelf of the Gulf of Mexico and deepwater Gulf of Mexico; and the ratio of reserves as of June 30, 2005 to 2005 expected production;
	•	the relative contributions of Mariner and the Forest Gulf of Mexico operations to the current and future financial performance of the combined company on a pro forma basis;

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	•	the report dated as of September 9, 2005, prepared by the management of Mariner, assessing the damage to the Gulf of Mexico assets of Mariner caused by Hurricane Katrina; and
	•	the report dated as of September 9, 2005, prepared by the management of Forest, assessing the damage to the Gulf of Mexico assets of the Forest Gulf of Mexico operations caused by Hurricane Katrina.

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	Valuation Analyses Used to Derive Implied Exchange Ratios

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				Implied
				Exchange
Valuation Methodology		Summary Description of Valuation Methodology		Ratio Range*
Net Asset Valuation Analysis		Net present valuation of after-tax cash flows generated by producing to exhaustion existing proved reserves, using selected hydrocarbon pricing scenarios and discount rates plus the evaluation of probable and possible reserves and certain other assets and liabilities
		— Case I Commodity Prices			0.84 - 1.11
		— Case II Commodity Prices			0.95 - 1.30
		— Case III Commodity Prices			0.88 - 1.14
Comparable Company Analysis		Market valuation benchmark based on trading multiples of selected comparable companies for selected financial and asset-based measures			0.78 - 1.14
Comparable Transactions Analysis		Market valuation benchmark based on consideration paid in selected comparable transactions			0.80 - 1.32
Exchange Ratio in the Merger					1.00*

*

Shares of Forest Energy Resources will be exchanged for shares of Mariner on a one-for-one basis. The exchange ratio represents the number of Mariner shares to be issued in the merger for each Forest Energy Resources share. As a result of this exchange ratio and the number of shares of Forest Energy Resources to be issued in the spin-off, Forest shareholders will receive approximately 0.8 shares of Mariner common stock for each share of Forest common stock they own or, in the case of Forest shareholders who would receive less than one full Mariner share in the merger, cash in lieu of such fractional share.

	Net Asset Valuation Analysis

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																											Escalation
			2005E				2006E				2007E				2008E				2009E				2010E				Thereafter
Natural Gas ($MMBtu)
Case I: All reserve classifications			$	5.00			$	5.00			$	5.00			$	5.00			$	5.00			$	5.00				0.0%
Case II:
	Proved developed producing reserves		$	9.24			$	8.89			$	8.29			$	7.85			$	7.47			$	7.14				0.0%
	All other reserve classifications		$	5.00			$	5.00			$	5.00			$	5.00			$	5.00			$	5.00				0.0%
Case III: All reserve classifications			$	9.24			$	8.89			$	8.29			$	7.85			$	7.47			$	7.14				0.0%
Oil ($/BBL)
Case I: All reserve classifications			$	45.00			$	45.00			$	45.00			$	45.00			$	45.00			$	45.00				0.0%
Case II:
	Proved developed producing reserves		$	64.06			$	64.81			$	62.71			$	60.55			$	59.15			$	58.45				0.0%
	All other reserve classifications		$	45.00			$	45.00			$	45.00			$	45.00			$	45.00			$	45.00				0.0%
Case III: All reserve classifications			$	64.06			$	64.81			$	62.71			$	60.55			$	59.15			$	58.45				0.0%

	Comparable Company Analysis

	•	Bois d’Arc Energy, Inc.
	•	Comstock Resources, Inc.
	•	Energy Partners, Ltd.
	•	The Houston Exploration Company
	•	Remington Oil and Gas Corporation
	•	Spinnaker Exploration Company
	•	Stone Energy Corporation
	•	W&T Offshore, Inc.

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	•	Bois d’Arc Energy, Inc.
	•	Energy Partners, Ltd.
	•	The Houston Exploration Company
	•	Remington Oil and Gas Corporation
	•	Spinnaker Exploration Company
	•	Stone Energy Corporation
	•	W&T Offshore, Inc.

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	Comparable Transactions Analysis

	•	Petrohawk Energy Corporation/ Mission Resources Corporation
	•	Cimarex Energy Company/ Magnum Hunter Resources, Inc.
	•	Noble Energy Inc./ Patina Oil & Gas Corporation
	•	EnCana Corporation/ Tom Brown, Inc.
	•	Kerr-McGee Corporation/ Westport Resources Corporation

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	•	Cimarex Energy Company/ Magnum Hunter Resources, Inc.
	•	Noble Energy Inc./ Patina Oil & Gas Corporation
	•	EnCana Corporation/ Tom Brown, Inc.
	•	Kerr-McGee Corporation/ Westport Resources Corporation

	Contribution Analysis

	Pro Forma Merger Consequences Analysis

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	General

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	Scope of the Discussion

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	•	a “U.S. holder” is a beneficial owner of Forest, Forest Energy Resources or Mariner common stock that is (1) an individual citizen or resident of the U.S., (2) a corporation or any other entity taxable as a corporation created or organized in or under the laws of the U.S. or of a state of the U.S. or the District of Columbia, (3) a trust (i) in respect of which a U.S. court is able to exercise primary supervision over the administration of the trust and one or more U.S. persons have the authority to control all substantive decisions of the trust or (ii) that was in existence on August 20, 1996 and validly elected to continue to be treated as a domestic trust, or (4) an estate that is subject to U.S. tax on its worldwide income from all sources;
	•	a “non-U.S. holder” is any holder of Forest, Forest Energy Resources or Mariner common stock other than a U.S. holder; and
	•	the term “U.S. tax” means U.S. federal income tax under the Internal Revenue Code of 1986, as amended.

	•	tax exempt organizations;
	•	financial institutions, insurance companies and broker-dealers;
	•	holders who hold their Forest, Forest Energy Resources or Mariner common stock, as applicable, as part of a hedge, straddle, wash sale, synthetic security, conversion transaction or other integrated investment comprised of Forest, Forest Energy Resources or Mariner common stock and one or more other investments;
	•	mutual funds;
	•	holders that have a functional currency other than the U.S. dollar;
	•	traders in securities who elect to apply a mark-to-market method of accounting;
	•	holders who acquired their shares in compensatory transactions;
	•	holders who are subject to the alternative minimum tax; or
	•	non-U.S. holders who are or have previously been engaged in the conduct of a trade or business in the U.S. or who have ceased to be U.S. citizens or to be taxed as resident aliens.

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	Material U.S. Tax Consequences of the Spin-Off

	•	a Forest shareholder will not recognize any income, gain or loss as a result of the spin-off;
	•	a Forest shareholder’s aggregate tax basis for his or her Forest common stock on which Forest Energy Resources common stock is distributed and the Forest Energy Resources common stock received by such shareholder in the spin-off will be the same as the tax basis of Forest common stock held by such shareholder immediately prior to the spin-off. A Forest shareholder’s aggregate tax basis will be allocated between his or her Forest common stock and Forest Energy Resources common stock received in the spin-off in proportion to the relative fair market value of the Forest common stock and Forest Energy Resources common stock on the spin-off date;
	•	a Forest shareholder’s holding period for the Forest Energy Resources common stock received in the spin-off will include the holding period of the Forest common stock on which the distribution is made; and
	•	Forest will not recognize any income, gain or loss on the spin-off, other than with respect to any “excess loss account” or “intercompany transaction” required to be taken into account by Forest under the Treasury regulations relating to consolidated returns. It is also possible that Forest may recognize income with respect to certain cash received from Forest Energy Resources under the distribution agreement.

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	Material U.S. Tax Consequences of the Merger

	•	Mariner receive an opinion from Baker Botts L.L.P., dated as of the effective date of the merger, to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code; and
	•	Forest and Forest Energy Resources receive an opinion from Weil, Gotshal & Manges LLP, tax counsel to Forest, dated as of the effective date of the merger, to the effect that the merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code.

	•	a Mariner stockholder will not recognize gain or loss pursuant to the merger, and such holder’s tax basis and holding period in Mariner common stock will not be affected by the merger;

	•	a Forest Energy Resources stockholder who exchanges Forest Energy Resources common stock solely for Mariner common stock in the merger will not recognize gain or loss except, as described below, to the extent of any cash received in lieu of fractional shares of Mariner common stock;
	•	the aggregate tax basis in the Mariner common stock a Forest Energy Resources stockholder receives in the merger (including any fractional shares for which cash is received) will be the same as his or her aggregate tax basis in the Forest Energy Resources common stock surrendered in the merger;
	•	the holding period of the Mariner common stock received in the merger by a holder of Forest Energy Resources common stock (including any fractional shares for which cash is received) will include the holding period of Forest Energy Resources common stock that such stockholder surrendered in the merger; and
	•	a Forest Energy Resources stockholder who receives fractional share proceeds as a result of the sale of shares of Mariner common stock by the transfer agent will be treated as if such fractional share had been received by the shareholder as part of the merger and then sold by such stockholder. Accordingly, such stockholder will recognize capital gain or loss equal to the difference between the cash so received and the portion of the tax basis in Mariner common stock that is allocable to such fractional share. Any such capital gain or loss will be treated as a long-term or short-term capital gain or loss based on the holder’s holding period for the Mariner common stock (as determined above). Non-U.S. holders who receive fractional share proceeds may be subject to withholding tax with respect to the fractional share proceeds under special rules governing the disposition of interests in a United States real property holding corporation.

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	Material U.S. Federal Tax Consequences to U.S. Holders of Holding and Disposing of Mariner Common Stock

	Distributions on Common Stock

	Sales or Dispositions of Common Stock

	Information Reporting and Backup Withholding

	U.S. Federal Estate Tax

	Material U.S. Federal Tax Consequences to Non-U.S. Holders of Holding and Disposing of Mariner Common Stock

	Distributions on Common Stock

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	•	in the case of Mariner common stock held by a foreign partnership, the certification requirement will generally be applied to the partners of the partnership and the partnership will be required to provide certain information;
	•	in the case of Mariner common stock held by a foreign trust, the certification requirement will generally be applied to the trust or the beneficial owners of the trust depending on whether the trust is a “foreign complex trust,” “foreign simple trust” or “foreign grantor trust” as defined in the U.S. Treasury Regulations; and
	•	look-through rules will apply for tiered partnerships, foreign simple trusts and foreign grantor trusts.

	Sales or Dispositions of Common Stock

	•	the gain is effectively connected with the non-U.S. holder’s conduct of a trade or business in the U.S. and, if an income tax treaty applies, is attributable to a permanent establishment maintained by the non-U.S. holder in the U.S.; in these cases, the gain will be taxed on a net income basis at the rates and in the manner applicable to U.S. persons, and if the non-U.S. holder is a foreign corporation, the branch profits tax described above may also apply;
	•	the non-U.S. holder is an individual who is present in the U.S. for 183 days or more in the taxable year of the disposition and meets other requirements; or
	•	Mariner is or has been a “United States real property holding corporation” for U.S. tax purposes at any time during the shorter of the five-year period ending on the date of disposition or the period that the non-U.S. holder held such Mariner common stock.

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	Information Reporting and Backup Withholding

	•	is a U.S. person for U.S. tax purposes;
	•	derives 50% or more of its gross income in specific periods from the conduct of a trade or business in the U.S.;
	•	is a “controlled foreign corporation” for U.S. tax purposes; or
	•	is a foreign partnership, if at any time during its tax year:

	•	one or more of its partners are U.S. persons who in the aggregate hold more than 50% of the income or capital interests in the partnership; or
	•	the foreign partnership is engaged in a U.S. trade or business,

	U.S. Federal Estate Tax

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	•	pursuant to an effective registration statement under the Securities Act;
	•	in conformity with the volume and other limitations of Rule 145 promulgated under the Securities Act; or
	•	in a transaction which, in the opinion of independent counsel reasonably satisfactory to Mariner or as described in a “no-action” or interpretative letter from the Staff of the SEC, is not required to be registered under the Securities Act.

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	•	our high-quality assets with geographic and geological diversity;
	•	our successful track record of finding and developing oil and gas reserves; and
	•	our depth of operating experience.

	•	Our deepwater projects have the potential to provide large reserves, high production volumes and substantial cash flow. Approximately 65 Bcfe of our undeveloped estimated proved reserves as of December 31, 2004, are located in our high-impact deepwater projects — Swordfish, Pluto, Rigel, Baccarat, and Daniel Boone. The Baccarat project commenced production in July 2005 (although production was shut-in due to Hurricane Rita and is expected to recommence in the first quarter of 2006), and the Swordfish project commenced production in October 2005. Notwithstanding delays caused primarily by 2005 hurricane activity, we believe Pluto and Rigel will commence production in the second quarter of 2006. Proved undeveloped reserves attributable to those projects have been recategorized as proved developed reserves. Daniel Boone is currently scheduled for production in 2008.
	•	The Gulf of Mexico is an area that offers substantial growth opportunities, and we expect to continue to generate shelf, deep shelf and deepwater Gulf of Mexico prospects. The Forest Gulf of Mexico assets will more than double our existing undeveloped acreage position to approximately 465,000 net acres and increase our total net leasehold acreage offshore to nearly 1 million acres, providing numerous exploration, exploitation and development opportunities. We believe the additional acreage also will provide increased exposure to farm-out opportunities from other oil and gas operators. Our team of geoscientists currently has access to seismic data from multiple, recent vintage 3-D seismic databases covering more than 6,600 blocks in the Gulf of Mexico that we intend to continue to use to develop prospects on acreage being evaluated for leasing and to develop and further refine prospects on our expanded acreage position. The combination of our undeveloped acreage position, inventory of

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		development prospects, seismic data and technical knowledge should enhance our ability to select projects with the greatest return potential for future development. We will also gain access to a significant infrastructure in the shelf that we believe will provide substantial cost efficiencies to the combined operations.
	•	Our West Texas assets provide stable cash flow and long-lived reserves, with significant development opportunities. In West Texas, during the three years ended December 31, 2004, we drilled 105 wells, all commercially successful, added approximately 76 Bcfe of estimated proved reserves, and increased our average daily production by more than 400%. Our 52 Bcfe of undeveloped estimated proved reserves in West Texas includes 162 locations. Our recent West Texas acquisition adds to our asset base an approximate 35% working interest in over 200 existing producing wells and, we believe, will provide future infill development opportunities, much like our Aldwell unit. This recent acquisition, in conjunction with our existing West Texas acreage, gives Mariner an inventory of multi-year development drilling opportunities.

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	•	reduce our concentration risk;
	•	provide many exploration, exploitation and development opportunities;
	•	enable us to increase the number of our internally-generated prospects;
	•	expand our sphere of influence and enhance our ability to participate in prospects generated by other operators; and
	•	add a significant cash flow generating resource that will improve our ability to compete effectively in the Gulf of Mexico and provide funding for acquisition projects.

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	Structure of the Merger

	Effective Time of the Merger

	Merger Consideration

	Cancellation of Certain Shares

	Procedure for Surrender of Certificates

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	Treatment of Certain Forest Stock Options

	•	the number of shares of Forest common stock subject to the portion of such option that is unexercisable immediately before the effective time, by
	•	the “option exchange ratio” described below,

	•	the average of the daily closing prices per share of Forest common stock for the last five trading days immediately preceding the effective time of the merger, by
	•	the average of the daily closing prices per share of Mariner common stock for the first five trading days following the effective time of the merger,

	Board of Directors and Officers of Mariner

	•	corporate existence, qualifications to conduct business and corporate standing and power;
	•	corporate authorization, enforceability and actions by the board of directors;
	•	capitalization;
	•	financial statements and undisclosed liabilities;
	•	absence of certain material changes or events since June 30, 2005;

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	•	governmental investigations and litigation;
	•	licenses and compliance with laws;
	•	the registration statements to be filed with the SEC and this proxy statement/ prospectus-information statement;
	•	information supplied to governmental authorities;
	•	compliance with environmental laws;
	•	tax matters;
	•	benefit plans;
	•	labor matters;
	•	intellectual property matters;
	•	material contracts;
	•	financial advisor opinion (given only by Mariner);
	•	payment of broker’s and finder’s fees in connection with the merger agreement and other transaction agreements;
	•	takeover statutes (given only by Mariner);
	•	certain findings of the board of directors to approve the merger;
	•	stockholder votes necessary to complete the merger;
	•	absence of requirement for Forest stockholder approval (given only by Forest);
	•	Forest Energy Resources stockholder approval (given only by Forest Energy Resources);
	•	payments to certain affiliated individuals or entities;
	•	title to, and sufficiency of, assets;
	•	loans made to third parties;
	•	oil and gas reserves; and
	•	derivative transactions.

	•	due organization and good standing;
	•	corporate power, authorization and validity of agreements;
	•	information supplied to governmental authorities;
	•	payment of broker’s and finder’s fees in connection with the merger agreement and other transaction agreements; and
	•	rights plan.

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	No Solicitation

	•	solicit, initiate, encourage, facilitate or induce any inquiry, proposal or offer with respect to an acquisition proposal;
	•	participate in any discussions or negotiations regarding, provide nonpublic information with respect to, or otherwise facilitate any acquisition proposal;
	•	engage in discussions with respect to an acquisition proposal;
	•	approve, endorse or recommend an acquisition proposal, except as provided in the merger agreement; or
	•	enter into any agreement related to any acquisition proposal, except as provided by the merger agreement.

	•	any purchase by any person, entity or group, as defined in Section 13(d) of the Exchange Act, of more than 15% of the total outstanding voting securities of Mariner;
	•	any tender or exchange offer that would result in any person, entity or group, as defined in Section 13(d) of the Exchange Act, owning 15% or more of the total outstanding voting securities of Mariner;
	•	any merger, consolidation, business combination or similar transaction involving Mariner;
	•	any sale, exchange, transfer, acquisition or disposition, or any lease or license outside of the ordinary course of business, of more than 15% of Mariner’s assets; or
	•	any liquidation of dissolution of Mariner.

	•	notify Forest and Forest Energy Resources orally and in writing of the material terms of the acquisition proposal, request or inquiry;
	•	identify to Forest and Forest Energy Resources the person making the acquisition proposal, request or inquiry;
	•	furnish to Forest and Forest Energy Resources copies of all written materials provided in connection with the acquisition proposal or inquiry;
	•	provide to Forest and Forest Energy Resources as promptly as practicable, both orally and in writing, all information reasonably necessary to keep Forest and Forest Energy Resources informed in all material respects of the status and details of the acquisition proposal, request or inquiry, including providing copies of written materials received from and provided to the third party making the acquisition proposal, request or inquiry; and

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	•	provide Forest and Forest Energy Resources 48 hours’ prior notice (or such lesser notice as is provided to Mariner’s directors) of any meeting of Mariner’s board of directors at which it will consider an acquisition proposal, unless shorter notice is provided to the board of directors, in which case Forest and Forest Energy Resources are to be provided the same notice.

	•	Mariner has complied with all of its non-solicitation and notification obligations in the merger agreement;
	•	in the good faith judgment of Mariner’s board of directors (after receiving the advice of its legal counsel and financial advisor), the acquisition proposal is a superior offer or is reasonably likely to result in a superior offer;
	•	concurrently with furnishing any nonpublic information, Mariner notifies Forest and Forest Energy Resources in writing of its intention to furnish nonpublic information and furnishes the same nonpublic information to Forest and Forest Energy Resources;
	•	concurrently with engaging in negotiations with the third party, Mariner notifies Forest and Forest Energy Resources in writing of its intent to enter into negotiations with the third party; and
	•	Mariner executes a customary confidentiality agreement with the third party with terms at least as restrictive as the confidentiality agreement between Forest and Mariner.

	•	Mariner stockholders have not already approved the merger and the merger agreement;
	•	Mariner notifies Forest and Forest Energy Resources in writing:

	•	that it has received a superior offer;
	•	of the terms and conditions of the superior offer;
	•	of the identity of the third party making the superior offer; and
	•	that it intends to change its recommendation that Mariner stockholders approve the merger and the manner in which it intends to do so;

	•	Mariner provides Forest and Forest Energy Resources with copies of all written materials delivered by Mariner to the third party making the superior offer that have not previously been provided to Forest and Forest Energy Resources, and Mariner has otherwise made available to Forest and Forest Energy Resources all materials and information made available to the third party; and
	•	Mariner has not breached any of the provisions of the merger agreement relating to acquisition proposals and superior offers.

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	Board of Directors Covenant to Call Stockholders’ Meeting and to Recommend the Merger

	Operations of Forest (in respect of the Forest Gulf of Mexico operations), Forest Energy Resources and Mariner Pending Closing

	•	declare or pay any dividends on or make other distributions in respect of its capital stock;
	•	split, combine or reclassify any of its capital stock or issue or authorize or propose the issuance of any other securities in respect of, in lieu of, or in substitution for, shares of its capital stock;
	•	redeem, repurchase or otherwise acquire (or permit any subsidiary to redeem, repurchase or otherwise acquire) any shares of its capital stock;
	•	issue, deliver or sell any shares of, or securities convertible into, its capital stock of any class, except, in the case of Mariner, the issuance of stock options with three-year vesting or restricted stock for up to 300,000 shares of Mariner common stock;
	•	amend its governing documents;

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	•	other than purchases from vendors or suppliers in the ordinary course of business consistent with past practice, exercises of preferential rights and, in the case of Mariner, certain specified transactions, engage in acquisitions valued at more than $25 million in the aggregate;
	•	other than product sales and other dispositions in connection with normal equipment maintenance or salvage in the ordinary course of business and consistent with past practice and permitted liens, dispose of assets valued at more than $10 million in the aggregate, except, in the case of Mariner, transactions permitted as described under “— No Solicitation” above;
	•	incur or guarantee indebtedness, other than, in the case of Forest Energy Resources, indebtedness incurred or guaranteed in connection with the spin-off, or, in the case of Mariner, up to $170 million pursuant to a new or amended credit agreement;
	•	fail to continue its capital expenditure program for exploration and development or fail to perform, to the extent reasonably practicable, all capital expenditures at an aggregate cost not exceeding 120% of the aggregate costs set forth in the capital expenditure program;
	•	make material changes to employment arrangements;
	•	fail to comply with any laws, ordinances or regulations or permit to expire or terminate without renewal any license that is necessary to the operation of the business, to the extent the same would result in a material adverse effect;
	•	adopt a plan of complete or partial liquidation or dissolution;
	•	change its fiscal year or make any material change in its methods of accounting except as required by the Financial Accounting Standards Board or changes in generally accepted accounting principles, or in response to comments made by the SEC with respect to any registration statement;
	•	amend any agreement or arrangement with any affiliates (including employees of Mariner and Forest Energy Resources) on terms materially less favorable than could be reasonably expected to have been obtained with an unaffiliated third party on an arm’s-length basis;
	•	except in the ordinary course of business consistent with past practice, modify, amend, terminate or renew any material contract or waive, release or assign any material rights or claims, in each case if the action would have a material adverse effect or impair in any material respect the party’s ability to perform its obligations under the merger agreement and other transaction agreements;
	•	waive any preferential rights;
	•	enter into any contract not in the ordinary course of business involving total consideration of $2 million or more with a term longer than one year, unless it can be terminated by it without penalty upon no more than 30 days’ prior notice;
	•	fail to maintain insurance in amounts and against risks and losses as are customary for companies engaged in their respective businesses, except, in the case of Mariner, self-insurance with respect to operators’ extra expense insurance, physical damage to wellsite real and personal property insurance and business interruption insurance;
	•	make or rescind any material express or deemed election relating to taxes unless the action will not materially and adversely affect that party on a going-forward basis;
	•	settle or compromise any material claim or controversy relating to taxes, except where the settlement or compromise will not result in a material adverse effect on that party;
	•	amend any material tax returns;
	•	change in any material respect any of its methods of reporting income or deductions for federal income tax purposes, except as may be required by applicable law or except for changes that are reasonably expected not to result in a material adverse effect on that party;

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	•	pay, discharge or satisfy any material claims, liabilities or obligations, other than the payment, discharge or satisfaction, in the ordinary course of business or, in the case of Mariner, in accordance with their terms, of liabilities reflected or reserved against in, or contemplated by, the most recent consolidated financial statements or incurred in the ordinary course of business;
	•	take or cause or permit to be taken any action that would disqualify the spin-off under the distribution agreement from constituting a tax-free spin-off or that would disqualify either the merger or the contribution of assets from Forest to Forest Energy Resources from constituting a tax-free reorganization;
	•	intentionally take or agree or commit to take any action that would result in any of the conditions set forth in the merger agreement not being satisfied at the effective time of the merger;
	•	enter into any derivative transaction or any fixed price commodity sales agreement with a term of more than 60 days; and
	•	agree or otherwise take any action inconsistent with the foregoing.

	Commercially Reasonable Efforts, Further Assurances

	Employee Benefit Plans

	•	will participate in Mariner benefit plans as of the effective time of the merger on a basis no less favorable than that applicable to similarly situated Mariner employees, and be granted full credit for all purposes under such plans for prior service with Forest and Forest Energy Resources and their affiliates before the effective time of the merger (except to the extent necessary to avoid duplication of benefits);
	•	will, if the effective time of the merger occurs in 2006, receive vacation benefits for 2006 that are equal to the employee’s accrued and unused vacation under Forest’s vacation policy as of the effective time of the merger plus any additional vacation entitlement the employee would have earned under the terms of Mariner’s vacation policy; and

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	•	will receive specified relocation benefits if, from the effective time of the merger to the later of June 30, 2006 or six months after the effective time of the merger, Mariner or a subsidiary of Mariner relocates the principal place of employment of the employee by 50 miles or more from the location of his or her principal place of employment immediately prior to the effective time of the merger.

	Directors’ and Officers’ Indemnification

	Litigation Defense

	Accounting Matters

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	Reorganization Treatment

	Letter of Credit

	•	completion of the spin-off in accordance with the distribution agreement;
	•	obtaining all material consents, approvals and authorizations of any governmental authority legally required for the consummation of the transactions contemplated by the merger agreement and the other transaction agreements;
	•	the expiration or termination of any applicable waiting period under the Hart-Scott-Rodino Act;
	•	the SEC having declared effective the registration statements of Mariner relating to the shares of Mariner common stock to be issued in connection with the merger;
	•	the approval for listing on the New York Stock Exchange or Nasdaq of the shares of Mariner common stock and such other shares required to be reserved for issuance in connection with the merger, subject to official notice of issuance;
	•	approval of the merger and adoption of the merger agreement by the Mariner stockholders at the meeting;
	•	the absence of a final and non-appealable injunction or other prohibition issued by a court or other governmental entity that restrains, enjoins or prohibits the spin-off or the merger;
	•	there being no action by a governmental authority pending to restrain, enjoin, prohibit or delay consummation of the transactions contemplated by the merger agreement, or to impose any material restrictions or requirements on the transactions contemplated by the merger agreement or on Forest Energy Resources or Mariner with respect to the transactions;
	•	there being no action taken and no statute, rule, regulation or executive order enacted, entered, promulgated or enforced by any governmental authority with respect to the merger that, individually or in the aggregate, would restrain, prohibit or delay the consummation of the merger or impose material restrictions or requirements on consummation of the merger or on Forest Energy Resources or Mariner with respect to the transactions;
	•	the performance by Forest, Forest Energy Resources and Mariner in all material respects of their respective covenants and agreements contained in the merger agreement and the truthfulness and correctness of the representations and warranties in the merger agreement in all respects, except in

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		each case where the failure to be true and correct, individually or in the aggregate, would not have a material adverse effect or to the extent specifically contemplated or permitted by the merger agreement; and
	•	Forest, Forest Energy Resources and Mariner having received an opinion from their respective counsel to the effect that the merger will be treated for federal income tax purposes as a reorganization.

	•	Forest having received any consents required from its bondholders; and
	•	Forest having received the consents required pursuant to its credit facility.

	•	Mariner having received the consents required pursuant to its credit facility; and
	•	Forest Energy Resources and/or Mariner having entered into a new or amended credit facility with available borrowing capacity sufficient to operate the Forest Gulf of Mexico operations and Mariner’s business after the closing of the merger transaction consistent with past practice.

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	Right to Terminate

	•	by mutual written consent of the parties;
	•	by any party:

	•	if the effective time of the merger has not occurred on or before March 31, 2006, except that a party may not terminate the merger agreement if the cause of the merger not being completed on or before such date resulted from the party’s failure to fulfill its obligations;
	•	if a court or other governmental entity issues a final and non-appealable injunction or otherwise prohibits the merger and the terminating party has used all commercially reasonable efforts to remove such injunction or prohibition; or
	•	if the adoption of the merger agreement and the approval of the transactions contemplated by the merger agreement by the Mariner stockholders is not obtained, except that Mariner may not terminate the merger agreement if the cause of the approval not being obtained resulted from the action or failure to act of Mariner and such action or failure to act constitutes a breach by Mariner of the provisions of the merger agreement relating to non-solicitation in any respect or a material breach by Mariner of any of the other covenants or agreements contained in the merger agreement;

	•	by Mariner:

	•	if either Forest or Forest Energy Resources fails to perform in any material respect any of its respective covenants or agreements contained in the merger agreement required to be performed at or prior to the effective time of the merger, or the respective representations and warranties of Forest or Forest Energy Resources in the merger agreement are or will become untrue in any respect at any time prior to the effective time of the merger and the failure to be true and correct, individually or in the aggregate, would have a material adverse effect on the Forest Gulf of Mexico operations, Forest Energy Resources or Mariner and has not been cured within 30 days after written notice was given to Forest and Forest Energy Resources of such failure or untruth; or
	•	if the board of directors of Mariner changes its recommendation that Mariner stockholders approve the merger in order to accept a superior offer, provided that:

	•	Mariner is not in breach of the provisions of the merger agreement relating to non-solicitation or in material breach of any other covenant or agreement contained in the merger agreement, and has not breached any of its representations and warranties contained in the merger agreement in any material respect;
	•	Forest has not made an offer that is at least favorable as the superior offer within three business days after Forest receives written notice of the superior offer;

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	•	the Mariner board of directors authorizes Mariner to enter into a binding written agreement with respect to the superior offer and notifies Forest and Forest Energy Resources of its intent to do so and provides a copy of the most current version of the agreement; and
	•	Mariner pays the termination fee and expense reimbursement;

	•	by Forest:

	•	if Mariner fails to perform in any material respect any of its covenants or agreements contained in the merger agreement required to be performed at or prior to the effective time of the merger, or the representations and warranties of Mariner in the merger agreement are or will become untrue in any respect at any time prior to the effective time of the merger and the failure to be true and correct, individually or in the aggregate, would have a material adverse effect on Mariner, the Forest Gulf of Mexico operations or Forest Energy Resources and has not been cured within 30 days after written notice was given to Mariner of such failure or untruth; or
	•	if the board of directors of Mariner (i) fails to reaffirm publicly its approval of the merger, as soon as reasonably practicable, and in no event within three business days after Forest’s request, or resolves not to reaffirm the merger, (ii) fails to include in this proxy statement/ prospectus-information statement its recommendation, without modification or qualification, that Mariner stockholders approve the merger, (iii) withholds, withdraws, amends or modifies its recommendation that Mariner stockholders approve the merger, (iv) changes its recommendation that Mariner stockholders approve the merger or (v) within ten business days after commencement, fails to recommend against acceptance of any tender or exchange offer for shares of Mariner common stock or takes no position with respect to any tender or exchange offer.

	Termination Fees and Expenses

	•	the other party’s failure to perform in any material respect any of its covenants or agreements contained in the merger agreement; or
	•	the representations and warranties of such other party in the merger agreement being or becoming untrue; and
	•	the failure to be true and correct, individually or in the aggregate, would have a material adverse effect on Forest Energy Resources, the Mariner business or Mariner and has not been cured within 30 days after written notice was given to such party of such failure or untruth,

	•	(i) either Forest or Mariner terminates the merger agreement as a result of the failure to obtain the requisite stockholder approval from Mariner stockholders, (ii) either Forest or Mariner terminates the merger agreement as a result of the effective time of the merger not occurring on or before March 31, 2006 or (iii) Forest terminates the merger agreement as a result of the failure of Mariner to perform in any material respect any of its covenants and agreements contained in the merger agreement, plus an acquisition proposal had been publicly announced prior to the termination and, within twelve months of the date of termination, Mariner either completes an acquisition proposal with a third party or enters into an agreement or recommends approval of any acquisition proposal that is subsequently completed (whether or not within the twelve-month period);
	•	Forest terminates the merger agreement as a result of the board of directors of Mariner (i) having failed to reaffirm publicly its approval of the merger, as soon as reasonably practicable, and in no event later than three business days, after request by Forest, or having resolved not to reaffirm the merger,

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		(ii) having failed to include in this proxy statement/ prospectus-information statement its recommendation, without modification or qualification, that Mariner stockholders approve the merger, (iii) having withheld, withdrawn, amended or modified its recommendation that Mariner stockholders approve the merger, (iv) having changed its recommendation that Mariner stockholders approve the merger or (v) within ten business days after commencement, having failed to recommend against acceptance of any tender or exchange offer for shares of Mariner common stock or takes no position with respect to any such tender or exchange offer; or
	•	Mariner terminates the merger agreement as a result of the board of directors of Mariner changing its recommendation that Mariner stockholders approve the merger in order to permit Mariner to accept a superior offer.

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	•	all real property interests, overriding royalty interests, reversionary interests, real or immovable property (including use and occupation rights, rights to pooled, communitized or unitized acreage, and platforms, pipelines and improvements), easements, inventory, hydrocarbons, equipment, personal or movable property, spare parts, contracts, books and records, proceeds, refunds, settlements, claims and current assets to the extent comprising a part of the Forest Gulf of Mexico operations;
	•	other assets of Forest and the subsidiaries of Forest to the extent specifically assigned by Forest or any subsidiaries pursuant to the distribution agreement; and
	•	all rights of Forest Energy Resources under the distribution agreement and the other agreements entered into in connection with the merger and the spin-off.

	•	all of the liabilities of the Forest Gulf of Mexico operations to the extent arising after June 30, 2005 and attributable to the conduct of the business after that date;
	•	legal obligations to plug, abandon, remove or retire platforms, pipelines, improvements, equipment, personal or movable property, fixtures and improvements comprising part of the Forest Gulf of Mexico assets, to the extent the obligation was previously disclosed to Mariner, arose after June 30, 2005 or was not known to Forest after due inquiry on the date of the distribution agreement;
	•	environmental liabilities arising from the conduct of the Forest Gulf of Mexico operations (subject to a monetary cap with respect to specified conditions), unless such liability was required to have been disclosed to Mariner prior to the execution of the merger agreement and was not so disclosed; and
	•	liabilities under specified derivatives contracts with an estimated fair value of $50.8 million as of June 30, 2005.

	•	minus revenue derived from the Forest Gulf of Mexico operations from June 30, 2005 through the date of the spin-off (which period is referred to as the “measurement period”);
	•	minus cash consideration from any sale of property, plant and equipment related to the Forest Gulf of Mexico assets during the measurement period;
	•	plus certain net assets and liabilities specified on the date of the distribution agreement;

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	•	plus or minus the net gas balancing assets or liabilities of the Forest Gulf of Mexico operations as of June 30, 2005;
	•	plus or minus the net settlement amounts in respect of settlements of gas imbalances effected during the measurement period;
	•	plus capital and operating expenditures attributable to the Forest Gulf of Mexico operations during the measurement period;
	•	plus an amount equal to hypothetical income taxes attributable to the Forest Gulf of Mexico operations during the measurement period;
	•	plus interest expense attributable to the Forest Gulf of Mexico operations during the measurement period;
	•	plus $1.6 million per month during the measurement period in respect of general and administrative expenses;
	•	plus an amount, not to exceed $7 million, in respect of the fees and expenses of Forest and Forest Energy Resources in connection with the merger and related transactions;
	•	plus or minus an amount equal to the change in working capital accounts (other than cash) of the Forest Gulf of Mexico operations during the measurement period.

	•	to pay, among other things, any losses or liabilities of Forest or its subsidiaries (including liabilities under the agreements entered into in connection with the merger and the spin-off);
	•	to transfer to Forest Energy Resources or any of its subsidiaries all of the assets to be transferred to Forest Energy Resources; and
	•	to perform any of its obligations under the distribution agreement.

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	•	obtaining all material consents, approvals and authorizations of any governmental authority that are legally required for the spin-off and other transactions contemplated by the other agreements entered into in connection with the spin-off and the merger;
	•	the absence of an injunction or other prohibition issued by a court or other governmental entity that restrains, enjoins or prohibits or otherwise imposes material restrictions on the spin-off or the merger;
	•	the SEC having declared effective the registration statement of Mariner relating to the shares of Mariner common stock to be issued into which shares of Forest Energy Resources common stock will be converted pursuant to the merger, of which this proxy statement/ prospectus-information statement forms a part;
	•	the approval for listing on the New York Stock Exchange or Nasdaq of the Mariner common stock and the other shares required to be reserved for issuance in connection with the merger, subject to official notice of issuance;
	•	the adoption of the merger agreement by the Mariner stockholders at the meeting;
	•	Forest having received an opinion from its tax counsel to the effect that the contribution will constitute a reorganization under Section 368(a) of the Internal Revenue Code and the distribution will qualify under Section 355 of the Internal Revenue Code;
	•	Forest having received the consents required from its bondholders;
	•	the performance by Mariner in all material respects of its covenants and agreements contained in the merger agreement required to be performed at or prior to the date of the spin-off; and
	•	the truthfulness and correctness of the representations and warranties of Mariner in the merger agreement in all respects, except as permitted by the merger agreement or where the failure to be true and correct would not have a material adverse effect.

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	Preparation and Filing of Tax Returns

	Liability for Taxes

	Transaction Taxes

	Continuing Covenants

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	•	a ruling from the Internal Revenue Service to the effect that the action contemplated would not affect the tax-free status of the spin-off,
	•	an opinion from a nationally recognized law firm both reasonably acceptable to Forest and Mariner to the effect that the action contemplated would not affect the tax-free status of the spin-off, or
	•	the agreement of both Forest and Mariner that such contemplated action would not affect the tax-free status of the spin-off.

	Miscellaneous

	•	sets forth the rights of the Forest Gulf of Mexico operations employees under certain of the Forest plans in which they previously participated, including with respect to the portion of their stock options that are exercisable at the effective time of the merger; and

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	•	provides for the assumption by Forest Energy Resources of certain liabilities of Forest relating to employees who are transferred to Forest Energy Resources, including the assumption of liabilities under Forest’s educational assistance plan and accrued vacation liabilities.

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		Applicable Margin
Usage as a %		LIBOR				Reference				Unused
Borrowing Base		Loans				Rate Loans				Fee
Less than 50%			1.25%				0.00%				0.375%
51% to 75%			1.50%				0.00%				0.375%
76% to 90%			1.75%				0.25%				0.250%
Greater than 90%			2.00%				0.50%				0.250%

	•	incur certain indebtedness;
	•	grant certain liens;
	•	merge or consolidate with another entity;
	•	sell unmortgaged property or other assets which generate proceeds in excess of 10% of the borrowing base;
	•	sell assets comprising collateral pledged to the lenders;
	•	make certain loans and investments;
	•	enter new lines of business; and
	•	permit certain trade payables to exceed 90 days.

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	•	consolidated current assets plus the unused borrowing base to consolidated current liabilities of not less than 1.0 to 1.0; and
	•	total debt to EBITDA of not more than 2.5 to 1.0.

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	•	incur indebtedness;
	•	grant certain liens;
	•	merge or consolidate with another entity;
	•	sell assets except in the ordinary course of business;
	•	make certain loans and investments;
	•	change the ownership of Forest Energy Resources; and
	•	permit trade payables to exceed 90 days.

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												Mariner
				Mariner				Merger				Pro Forma
				Historical				Adjustments(1)				Combined
				(In thousands)
ASSETS
Current Assets:
	Cash and cash equivalents			$	4,564			$	—			$	4,564
	Receivables				50,259				—				50,259
	Deferred tax asset				30,480				—				30,480
	Prepaid expenses and other				18,732				2,874	(2)			21,606
		Total current assets			104,035				2,874				106,909
Property and Equipment, net					393,258				1,463,846	(3)			1,857,104
Goodwill					—				142,000	(3)			142,000
Other Assets, net of amortization					4,916				7,597	(2)			12,513
		TOTAL ASSETS		$	502,209			$	1,616,317			$	2,118,526
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current Liabilities:
	Accounts payable			$	14,573			$	—			$	14,573
	Accrued liabilities				88,993				32,491	(2)			121,484
	Accrued interest				141				—				141
	Derivative liability				76,902				108,031	(2)			184,933
		Total current liabilities			180,609				140,522				321,131
Long-Term Liabilities:
	Abandonment liability				26,314				116,203	(2)			142,517
	Deferred income tax				6,468				168,852	(4)			175,320
	Derivative liability				28,221				17,203	(2)			45,424
	Bank debt				75,000				200,000	(5)			275,000
	Note payable				4,000				—				4,000
	New debt				—				—				—
	Other long-term liabilities				3,000				—				3,000
		Total long-term liabilities			143,003				502,258				645,261
Stockholders’ Equity:
	Common stock				4				5	(6)			9
	Additional paid-in capital				171,667				973,532	(3)			1,145,199
	Unearned compensation				(14,548	)			—				(14,548	)
	Accumulated other comprehensive (loss)				(67,708	)			—				(67,708	)
	Accumulated retained earnings				89,182				—				89,182
		Total stockholders’ equity			178,597				973,537				1,152,134
		TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY		$	502,209			$	1,616,317			$	2,118,526

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								Forest Energy								Mariner
				Mariner				Resources, Inc.				Merger				Pro Forma
				Historical				Historical(7)				Adjustments(1)				Combined
				(In thousands)
Revenues:
	Oil & gas sales			$	148,492			$	326,722			$	—			$	475,214
	Other revenues				2,753				—				—				2,753
		Total revenues			151,245				326,722				—				477,967
Costs and Expenses:
	Lease operating expenses				20,170				59,379				—				79,549
	Transportation expenses				1,697				2,484				—				4,181
	General and administrative expenses				26,726				—				—				26,726
	Depreciation, depletion and amortization				43,457				—				201,255	(8)			244,712
	Impairment of production equipment held for use				498				—				—				498
		Total costs and expenses			92,548				61,863				201,255				355,666
OPERATING INCOME					58,697				264,859				(201,255	)			122,301
Interest:
	Income				696								—				696
	Expense, net of amounts capitalized				(5,416	)							(8,010	)(9)			(13,426	)
Income before taxes					53,977								(209,265	)			109,571
Provision for income taxes					(18,414	)							(19,936	)(10)			(38,350	)
NET INCOME					35,563								(229,201	)			71,221
Earnings per share:
Net Income per share — basic					1.10												0.86
Net Income per share — diluted					1.07												0.85
Weighted average shares outstanding — basic					32,438,240								50,637,010				83,075,250
Weighted average shares outstanding — diluted					33,312,831								50,637,010				83,949,841

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								Forest Energy								Mariner
				Mariner				Resources, Inc.				Merger				Pro Forma
				Historical				Historical(7)				Adjustments(1)				Combined
				(In thousands)
Revenues:
	Oil & gas sales			$	214,187			$	453,139			$	—			$	667,326
	Other revenues				—				—				—				—
		Total revenues			214,187				453,139				—				667,326
Costs and Expenses:
	Lease operating expenses				25,484				81,627				—				107,111
	Transportation expenses				3,029				2,175				—				5,204
	General and administrative expenses				8,772				—				—				8,772
	Depreciation, depletion and amortization				64,911				—				303,261	(8)			368,172
	Impairment of production equipment held for use				957				—				—				957
		Total costs and expenses			103,153				83,802				303,261				490,216
OPERATING INCOME					111,034				369,337				(303,261	)			177,110
Interest:
	Income				316								—				316
	Expense, net of amounts capitalized				(6,050	)							(7,840	)(9)			(13,890	)
Income before taxes					105,300								(311,101	)			163,536
Provision for income taxes					(36,855	)							(20,383	)(10)			(57,238	)
NET INCOME					68,445								(331,484	)			106,298
Earnings per share:
Net Income per share — basic					2.30