FORM OF WARRANT AGREEMENT

EXHIBIT 4.3

[FORM OF WARRANT AGREEMENT]

GSC ACQUISITION COMPANY

and

AMERICAN STOCK TRANSFER & TRUST COMPANY, as Warrant Agent

_______________________________

WARRANT AGREEMENT

Dated as of [ ], 2007

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      WARRANT AGREEMENT dated as of [ ], 2007, between GSC Acquisition Company, a Delaware corporation (the " Company "), and American Stock Transfer & Trust Company, a New York corporation, as Warrant Agent (the " Warrant Agent ").

      WHEREAS, the Company proposes to issue (i) 4,000,000 warrants to be offered in a private placement bearing the legend set forth in Exhibit B hereto (the " Founder’s Warrants "), and (ii) up to 25,156,250 warrants to be offered pursuant to a registration statement filed with the Securities and Exchange Commission (the " Public Warrants " and together with the Founder’s Warrants, the " Warrants "), which in each case entitle the holders thereof to purchase shares of common stock of the Company, $0.001 par value per share (" Common Stock ," and the Common Stock issuable on exercise of the Warrants, the " Warrant Shares ");

      WHEREAS, the Company desires the Warrant Agent to act on behalf of the Company, and the Warrant Agent is willing so to act, in connection with the issuance, transfer, exchange and exercise of Warrants and other matters as provided herein;

      NOW, THEREFORE, in consideration of the premises and the mutual agreements herein set forth, the parties hereto agree as follows:

      SECTION 1. Appointment of Warrant Agent. The Company hereby appoints the Warrant Agent to act as agent for the Company in accordance with the instructions set forth hereinafter in this Agreement, and the Warrant Agent hereby accepts such appointment.

      SECTION 2. Warrant Certificates. The certificates evidencing the Warrants (the " Warrant Certificates ") to be delivered pursuant to this Agreement shall be in registered form only and shall be substantially in the form set forth in Exhibit A attached hereto.

      SECTION 3. Execution of Warrant Certificates. Warrant Certificates shall be signed on behalf of the Company by its Chairman of the Board or its President or Chief Executive Officer or a Vice President and by its Secretary or an Assistant Secretary. Each such signature upon the Warrant Certificates may be in the form of a facsimile signature of the present or any future Chairman of the Board, President, Chief Executive Officer, Vice President, Secretary or Assistant Secretary and may be imprinted or otherwise reproduced on the Warrant Certificates and for that purpose the Company may adopt and use the facsimile signature of any person who shall have been Chairman of the Board, President, Chief Executive Officer, Vice President, Secretary or Assistant Secretary, notwithstanding the fact that at the time the Warrant Certificates shall be countersigned and delivered or disposed of he or she shall have ceased to hold such office.

      In case any officer of the Company who shall have signed any of the Warrant Certificates shall cease to be such officer before the Warrant Certificates so signed shall have been countersigned by the Warrant Agent, or disposed of by the Company, such Warrant Certificates nevertheless may be countersigned and delivered or disposed of as though such person had not ceased to be such officer of the Company; and any Warrant Certificate may be signed on behalf of the Company by any person who, at the actual date of the execution of such Warrant Certificate, shall be a proper officer of the Company to sign such Warrant Certificate,

although at the date of the execution of this Warrant Agreement any such person was not such officer.

      Warrant Certificates shall be dated the date of countersignature by the Warrant Agent.

      SECTION 4. Registration and Countersignature. The Warrant Agent, on behalf of the Company, shall hold the Founder’s Warrants unnumbered and unregistered and the Public Warrants pre-numbered and unregistered.

      Warrant Certificates shall be countersigned by the Warrant Agent and shall not be valid for any purpose unless so countersigned. The Warrant Agent shall, upon written instructions of the Chairman of the Board, the President or Chief Executive Officer, a Vice President, the Treasurer or the Chief Financial Officer of the Company, countersign, issue and deliver Warrants as provided in this Agreement.

      The Company and the Warrant Agent may deem and treat the registered holder(s) of the Warrant Certificates as the absolute owner(s) thereof (notwithstanding any notation of ownership or other writing thereon made by anyone), for all purposes, and neither the Company nor the Warrant Agent shall be affected by any notice to the contrary.

      SECTION 5. Registration of Transfers and Exchanges; Transfer Restrictions. The Warrant Agent shall from time to time, subject to the limitations of this Section 5, register the transfer of any outstanding Warrant Certificates upon the records to be maintained by it for that purpose, upon surrender thereof duly endorsed or accompanied (if so required by the Warrant Agent) by a written instrument or instruments of transfer in form satisfactory to the Warrant Agent, duly executed by the registered holder or holders thereof or by the duly appointed legal representative thereof or by a duly authorized attorney. Upon any such registration of transfer, a new Warrant Certificate shall be issued to the transferee(s) and the surrendered Warrant Certificate shall be cancelled by the Warrant Agent. Cancelled Warrant Certificates shall thereafter be disposed of by the Warrant Agent in its customary manner.

      The Founder’s Warrants may not be sold or transferred prior to the date upon which the Company completes an acquisition, through a merger, capital stock exchange, asset acquisition, stock purchase, reorganization or other similar business combination, of one or more businesses or assets in the energy industry (its " Initial Business Combination ") (such date, the " Transfer Restriction Termination Date ") except to a Permitted Transferee who agrees in writing with the Company to be subject to such transfer restrictions. As used herein, " Permitted Transferee " means (a) any officer, director of employee of the Company; or (b) any other Person associated with GSC Group as such term is defined in the registration statement relating to the final prospectus relating to the offering of Public Warrants filed with the Securities and Exchange Commission.

      The holders of any Founder’s Warrant or Warrant Shares issued upon exercise of any Founder’s Warrant further agree prior to any transfer of such securities, to give written

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notice to the Company expressing its desire to effect such transfer and describing briefly the proposed transfer. Upon receiving such notice, the Company shall present copies thereof to its counsel and the holder agrees not to make any disposition of all or any portion of such securities unless and until:

      (a) there is then in effect a registration statement under the Securities Act covering such proposed disposition and such disposition is made in accordance with such registration statement, in which case the legends set forth in Exhibit B or Section 6(c) hereof, as the case may be (collectively the "Legends") with respect to such securities sold pursuant to such registration statement shall be removed; or

      (b) if reasonably requested by the Company, (A) the holder shall have furnished the Company with an opinion of counsel, reasonably satisfactory to the Company, that such disposition will not require registration of such Securities under the Securities Act, (B) the Company shall have received customary representations and warranties regarding the transferee that are reasonably satisfactory to the Company signed by the proposed transferee and (C) the Company shall have received an agreement by such transferee to the restrictions contained in the Legends.

      Each Public Warrant shall initially be issued together with one share of Common Stock as a unit (a " Unit "). The shares of Common Stock and Public Warrants comprising a Unit shall not be separately transferable before the later of (i) five Business Days following the earlier to occur of the expiration of the underwriters’ over-allotment option included in the underwriting agreement with respect to the publicly offered Units and the exercise of such option in full and (ii) the date on which the Company has filed a Form 8-K with the Securities and Exchange Commission containing an audited balance sheet reflecting the Company’s receipt of the gross proceeds of the offering of the Units and has issued a press release announcing when such separate trading will begin (the later of such dates, the " Detachment Date "). Prior to the Detachment Date, Public Warrants may be transferred or exchanged only together with the Unit in which such Public Warrant is included, and only for the purpose of effecting, or in conjunction with, a transfer or exchange of such Unit. Furthermore, prior to the Detachment Date, each transfer of a Public Unit on the register relating to such Units shall operate also to transfer the Public Warrants included in such Unit.

      Subject to the terms of this Agreement, Warrant Certificates may be exchanged at the option of the holder(s) thereof, when surrendered to the Warrant Agent at its principal corporate trust office, which is currently located at the address listed in Section 17 hereof, for another Warrant Certificate or other Warrant Certificates of like tenor and representing in the aggregate a like number of Warrants. Any holder desiring to exchange a Warrant Certificate shall deliver a written request to the Warrant Agent, and shall surrender, duly endorsed or accompanied (if so required by the Warrant Agent) by a written instrument or instruments of transfer in form satisfactory to the Warrant Agent, the Warrant Certificate or Certificates to be so exchanged. Warrant Certificates surrendered for exchange shall be cancelled by the Warrant Agent. Such cancelled Warrant Certificates shall then be disposed of by such Warrant Agent in its customary manner.

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      The Warrant Agent is hereby authorized to countersign, in accordance with the provisions of this Section 5 and of Section 4 hereof, the new Warrant Certificates required pursuant to the provisions of this Section 5.

      SECTION 6. Terms of Warrants.

      (a) Exercise Price and Exercise Period.

      The initial exercise price per share at which Warrant Shares shall be purchasable upon the exercise of Warrants (the " Exercise Price ") shall be $6.00 per share, and each Warrant shall be initially exercisable to purchase one share of Common Stock.

      Subject to the terms of this Agreement (including without limitation Section 6(d) below), each Warrant holder shall have the right, which may be exercised commencing at the opening of business on the first day of the applicable Warrant Exercise Period set forth below and until 5:00 p.m., New York City time, on the last day of such Warrant Exercise Period, to receive from the Company the number of fully paid and nonassessable Warrant Shares which the holder may at the time be entitled to receive on exercise of such Warrants and payment of the Exercise Price then in effect for such Warrant Shares. No adjustments as to dividends will be made upon exercise of the Warrants.

      The " Warrant Exercise Period " shall commence (subject to Section 6(d) below), on the later of:

      (A) the date that is 13 months after the closing of the sale of the Warrants and

      (B) the date on which the Company completes its Initial Business Combination

      and shall end on the earlier of:

      (i) the date that is four years from the date of the final prospectus for the offering of the Public Warrants; and

      (ii) the Business Day preceding the date on which such Warrants are redeemed pursuant to Section 6(b) below or expire pursuant to Section 6(e) below.

      The " Closing Price " of the Common Stock on any date of determination means;

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      Each Warrant not exercised prior to 5:00 p.m., New York City time, on the last day of the Warrant Exercise Period shall become void and all rights thereunder and all rights in respect thereof under this Agreement shall cease as of such time.

      (b) Redemption of Warrants.

      The Company may call the Warrants for redemption, in whole and not in part, at a price of $.01 per Warrant, upon not less than 30 days’ prior written notice of redemption to each Warrant holder, at any time after such Warrants have become exercisable pursuant to Section 6(a), if, and only if, (i) the Closing Price has equaled or exceeded $11.50 per share for any 20 trading days within a 30-trading-day period ending on the third Business Day prior to the notice of redemption to Warrant holders and (ii) at all times between the date of such notice of redemption and the redemption date a registration statement is in effect covering the Warrant Shares issuable upon exercise of the Warrants and a current prospectus relating to those Warrant Shares is available.

      Notwithstanding the foregoing, no Founder’s Warrants shall be redeemable at the option of the Company so long as they are held by GSC Secondary Interest Fund, LLC or a Permitted Transferee; provided that the fact that one or more Founder’s Warrants are non-redeemable because they are held by GSC Secondary Interest Fund, LLC or a Permitted Transferee shall not affect the Company’s right to redeem the Public Warrants and all Founder’s Warrants that are not held by GSC Secondary Interest Fund, LLC or a Permitted Transferee pursuant to the preceding paragraph.

      (c) Exercise Procedure.

      A Warrant may be exercised upon surrender to the Company at the principal stock transfer office of the Warrant Agent, which is currently located at the address listed in Section 17 hereof, of the certificate or certificates evidencing the Warrants to be exercised with the form of election to purchase on the reverse thereof duly filled in and signed and such other documentation as the Warrant Agent may reasonably request, and upon payment to the Warrant

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Agent for the account of the Company of the Exercise Price (adjusted as herein provided if applicable) for the number of Warrant Shares in respect of which such Warrants are then exercised. Payment of the aggregate Exercise Price shall be made in cash or by certified or official bank check payable to the order of the Company in New York Clearing House Funds, or the equivalent thereof. In no event will any Warrants be settled on a net cash basis.

      Subject to the provisions of Section 7 hereof, upon such surrender of Warrants and payment of the Exercise Price, the Company shall issue and cause to be delivered with all reasonable dispatch to and in such name or names as the Warrant holder may designate, a certificate or certificates for the number of full Warrant Shares issuable upon the exercise of such Warrants together with cash as provided in Section 12 hereof. Such certificate or certificates shall be deemed to have been issued and any person so designated to be named therein shall be deemed to have become a holder of record of such Warrant Shares as of the date of the surrender of such Warrants and payment of the Exercise Price.

      The Warrants shall be exercisable, at the election of the holders thereof, either in full or from time to time in part and, in the event that a certificate evidencing Warrants is exercised in respect of fewer than all of the Warrant Shares issuable on such exercise at any time prior to the date of expiration of the Warrants, a new certificate evidencing the remaining Warrant or Warrants will be issued, and the Warrant Agent is hereby irrevocably authorized to countersign and to deliver the required new Warrant Certificate or Certificates pursuant to the provisions of this Section 6 and of Section 4 hereof, and the Company, whenever required by the Warrant Agent, shall supply the Warrant Agent with Warrant Certificates duly executed on behalf of the Company for such purpose. The Warrant Agent may assume that any Warrant presented for exercise is permitted to be so exercised under applicable law and shall have no liability for acting in reliance on such assumption.

      All Warrant Certificates surrendered upon exercise of Warrants shall be canceled by the Warrant Agent. Such canceled Warrant Certificates shall then be disposed of by the Warrant Agent in its customary manner. The Warrant Agent shall account promptly to the Company with respect to Warrants exercised and concurrently pay to the Company all monies received by the Warrant Agent for the purchase of the Warrant Shares through the exercise of such Warrants.

      The Warrant Agent shall keep copies of this Agreement and any notices given or received hereunder available for inspection by the holders with reasonable prior written notice during normal business hours at its office. The Company shall supply the Warrant Agent from time to time with such numbers of copies of this Agreement as the Warrant Agent may request.

      Certificates evidencing Warrant Shares issued upon exercise of a Founder’s Warrant shall contain the following legend:

      THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAW, AND MAY NOT BE OFFERED, SOLD, TRANSFERRED OR

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OTHERWISE DISPOSED OF UNLESS REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND ANY APPLICABLE STATE SECURITIES LAWS OR AN EXEMPTION FROM SUCH REGISTRATION IS AVAILABLE.

      SECURITIES EVIDENCED BY THIS CERTIFICATE WILL BE ENTITLED TO REGISTRATION RIGHTS UNDER A REGISTRATION RIGHTS AGREEMENT TO BE EXECUTED BY THE COMPANY.

      (d) Registration Requirement. Notwithstanding anything else in this Section 6, no Warrant (including any Founder’s Warrant) may be exercised unless at the time of exercise (i) a registration statement covering the Warrant Shares to be issued upon exercise (other than Warrant Shares to be issued upon exercise of any Founder’s Warrant) is effective under the Act and (ii) a prospectus thereunder relating to the Warrant Shares (other than Warrant Shares to be issued upon exercise of any Founder’s Warrant) is current, and the Company shall use its best efforts to have a registration statement in effect covering Warrant Shares issuable upon exercise of the Warrants (other than Warrant Shares to be issued upon exercise of any Founder’s Warrant) from the date the Warrants become exercisable and to maintain a current prospectus relating to those Warrant Shares until the Warrants expire or are redeemed. In the event that, at the end of the Warrant Exercise Period, a registration statement covering the Warrant Shares to be issued upon exercise (other than Warrant Shares to be issued upon exercise of any Founder’s Warrant) is not effective under the Act, all the rights of holders hereunder shall terminate and all of the Warrants shall expire worthless. In no event shall the Warrants be settled on a net cash basis during the Warrant Exercise Period nor shall the Company be required to issue unregistered shares upon the exercise of any Warrant that is not a Founder’s Warrant.

      (e) Expiry Upon Liquidation of Trust Account. If the Company is dissolved because it fails to effect an Initial Business Combination, all of the rights of holders hereunder shall terminate and all of the Warrants shall expire worthless.

      SECTION 7. Payment of Taxes. The Company will pay all documentary stamp taxes attributable to the initial issuance of Warrant Shares upon the exercise of Warrants; provided , however , that the Company shall not be required to pay any tax or taxes which may be payable in respect of any transfer involved in the issue of any Warrant Certificates or any certificates for Warrant Shares in a name other than that of the registered holder of a Warrant Certificate surrendered upon the exercise of a Warrant, and the Company shall not be required to issue or deliver such Warrant Certificates unless or until the person or persons requesting the issuance thereof shall have paid to the Company the amount of such tax or shall have established to the satisfaction of the Company that such tax has been paid.

      SECTION 8. Mutilated or Missing Warrant Certificates. In case any of the Warrant Certificates shall be mutilated, lost, stolen or destroyed, the Company shall issue and the Warrant Agent shall countersign, in exchange and substitution for and upon cancellation of the mutilated Warrant Certificate, or in lieu of and substitution for the Warrant Certificate lost, stolen or destroyed, a new Warrant Certificate of like tenor and representing an equivalent number of Warrants, but only upon receipt of evidence satisfactory to the Company and the

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Warrant Agent of such loss, theft or destruction of such Warrant Certificate and indemnity, also satisfactory to the Company and the Warrant Agent. Applicants for such new Warrant Certificates must pay such reasonable charges as the Company may prescribe.

      SECTION 9. Reservation of Warrant Shares. The Company will at all times reserve and keep available, free from preemptive rights, out of the aggregate of its authorized but unissued Common Stock or its authorized and issued Common Stock held in its treasury, for the purpose of enabling it to satisfy any obligation to issue Warrant Shares upon exercise of Warrants, the maximum number of shares of Common Stock which may then be deliverable upon the exercise of all outstanding Warrants. The Warrant Agent shall have no duty to verify availability of such shares set aside by the Company.

      The Company or, if appointed, the transfer agent for the Common Stock (the " Transfer Agent ") and every subsequent transfer agent for any shares of the Company’s Common Stock issuable upon the exercise of any of the Warrants will be irrevocably authorized and directed at all times to reserve such number of authorized shares as shall be required for such purpose. The Company will keep a copy of this Agreement on file with the Transfer Agent and with every subsequent transfer agent for any shares of the Company’s Common Stock issuable upon the exercise of the Warrants. The Warrant Agent is hereby irrevocably authorized to requisition from time to time from such Transfer Agent the stock certificates required to honor outstanding Warrants upon exercise thereof in accordance with the terms of this Agreement. The Company will supply such Transfer Agent with duly executed certificates for such purposes and will provide or otherwise make available any cash which may be payable as provided in Section 12 hereof. The Company will furnish such Transfer Agent a copy of all notices of adjustments and certificates related thereto, transmitted to each holder pursuant to Section 13 hereof.

      Before taking any action which would cause an adjustment pursuant to Section 11 hereof to reduce the Exercise Price below the then par value (if any) of the Warrant Shares, the Company will take any commercially reasonable corporate action which may, in the opinion of its counsel (which may be counsel employed by the Company), be necessary in order that the Company may validly and legally issue fully paid and nonassessable Warrant Shares at the Exercise Price as so adjusted.

      The Company covenants that all Warrant Shares which may be issued upon exercise of Warrants will, upon payment of the Exercise Price therefor and issue, be fully paid, nonassessable, free of preemptive rights and free from all taxes, liens, charges and security interests with respect to the issue thereof.

      SECTION 10. Obtaining Stock Exchange Listings. The Company will from time to time take all commercially reasonable actions which may be necessary so that the Warrant Shares, immediately upon their issuance upon the exercise of Warrants, will be listed on the principal securities exchanges and markets within the United States of America, if any, on which other shares of Common Stock are then listed.

      SECTION 11. Adjustment of Number of Warrant Shares.

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      The number of Warrant Shares issuable upon the exercise of each Warrant is subject to adjustment from time to time upon the occurrence of the events enumerated in this Section 11. For purposes of this Section 11, " Common Stock " means shares now or hereafter authorized of any class of common stock of the Company and any other stock of the Company, however designated, that has the right (subject to any prior rights of any class or series of preferred stock) to participate in any distribution of the assets or earnings of the Company without limit as to per share amount.

      (a) Adjustment for Change in Capital Stock.

      If the Company:

      (1) pays a dividend or makes a distribution on its Common Stock in either case in shares of its Common Stock;

      (2) subdivides its outstanding shares of Common Stock into a greater number of shares;

      (3) combines its outstanding shares of Common Stock into a smaller number of shares;

      (4) makes a distribution on its Common Stock in shares of its capital stock other than Common Stock; or

      (5) issues by reclassification of its Common Stock any shares of its capital stock,

then the number of shares of Common Stock issuable upon exercise of each Warrant immediately prior to such action shall be proportionately adjusted so that the holder of any Warrant thereafter exercised shall receive the aggregate number and kind of shares of capital stock of the Company which he would have owned immediately following such action if such Warrant had been exercised immediately prior to such action.

      The adjustment shall become effective immediately after the record date in the case of a dividend or distribution and immediately after the effective date in the case of a subdivision, combination or reclassification.

      Such adjustment shall be made successively whenever any event listed above shall occur.

      (b) Adjustment for Rights Issue.

      If the Company distributes any rights, options or warrants to all holders of its Common Stock entitling them to purchase shares of Common Stock at a price per share less than the Closing Price per share on the Business Day immediately preceding the ex-dividend date for such distribution of rights, options or warrants, the number of shares of Common Stock issuable upon exercise of each Warrant shall be adjusted in accordance with the formula:

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