AMENDMENT TO COMBINATION AGREEMENT

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Exhibit 10.6

This Amendment to Combination Agreement (this "Amendment") is entered into as of September 19, 2005, by and among Xxxxxx Oil Properties, Inc., an Oklahoma corporation ("SOP"), all the shareholders of SOP as listed on the signature page to this Agreement, Xxxxxx Energy Management, Ltd., a Texas limited partnership ("Management"), all the limited partners of Management as listed on the signature page to this Agreement, Xxxxxx Energy, Ltd., a Texas limited partnership ("Xxxxxx Ltd."), all the limited partners of Xxxxxx Ltd. as listed on the signature page to this Agreement, and Xxxxxx Energy, Inc., a Delaware corporation ("Newco"). The shareholders (and limited partners after the merger described below) of SOP and the limited partners of Management and Xxxxxx Ltd. (other than SOP) are collectively referred to as the "Owners".

RECITALS

The parties hereto entered into that certain Combination Agreement dated as of August 1, 2005 (the "Original Agreement"), pursuant to which the Owners agreed to exchange their ownership interests in SOP, Management and Xxxxxx Ltd. for stock in Newco through the series of transactions contemplated therein.

The parties desire to amend the Original Agreement to specify (i) the number of shares to be issued to each Owner in exchange for the transfers that take place pursuant to the Original Agreement and (ii) the number of shares to be sold by certain of the Owners in the Private Offering.

Now, therefore, in consideration of the premises and the mutual covenants and agreements contained herein and in the Original Agreement, and intending to be legally bound hereby, the parties agree as follows:

Section 1 Definitions. Capitalized terms used and not otherwise defined in this Amendment shall have the definitions given them in the Original Agreement. From and after the date hereof, all references to the "Agreement" in the Original Agreement shall mean the Original Agreement as amended by this Amendment.

Section 2 Amendment of Section 1.3. Section 1.3 of the Original Agreement is hereby amended and restated to read in its entirety as follows:

"Section 1.3 Receipt of Stock in Newco. The parties hereto acknowledge that the transactions described in this Agreement constitute "Capital Transactions" and the proceeds thereof constitute "Capital Proceeds" as defined in Xxxxxx Ltd.'s Partnership Agreement. In exchange for the transfers described above, Newco will issue the number of shares of Newco common stock to each Owner set forth beside such Owner's name on Schedule II attached hereto; provided, however, that the Reserved Class B Interests that were to be issued to members of management under Management's Partnership Agreement, but have not been specifically allocated, will become reserved shares (the "Unallocated Class B Interest Shares") retained by Newco for future issuance in accordance with the Xxxxxx Energy, Inc. 2005 Restricted Stock Plan (the "Newco Restricted Stock Plan") and, independent of the calculation referred to above, shall be fixed in number at 226,608 shares. The Unallocated Class B Interest Shares would otherwise have been issued to Owners of SOP by virtue of SOP's ownership of Class B Partnership Interests in Management as of the Closing. Shares of Newco common stock issued in exchange for the Class B Partnership Interests in Management that were granted to management employees in May 2005 and that are subject to forfeiture restrictions as of the Closing shall be issued pursuant to the Newco Restricted Stock Plan and such shares of Newco common stock shall be subject to the same forfeiture restrictions as

were in effect with respect to such Class B Partnership Interests prior to the Closing. Shares of Newco common stock issued in exchange for Class B Partnership Interests in Management that were issued to management employees prior to May 2005 shall not be subject to forfeiture and shall be fully vested."

Section 3 Addition of Section 1.13. The Original Agreement is hereby amended to add a new Section 1.13 to read in its entirety as follows:

"Section 1.13 Selling Shareholders. As part of the Private Offering, each Owner listed on Schedule III attached hereto will offer and sell, first, the number of shares of Newco common stock set forth beside such Owner's name under the heading "Base Amount Shares," and, second, pursuant to exercise of an option to cover additional allotments, the number of shares of Newco common stock set forth beside such Owner's name under the heading "Additional Allotment Shares."

Section 4 Amendments to Schedules. Schedule II to the Original Agreement is hereby amended and restated to read in its entirety as set forth on Schedule II attached to this Amendment. The Original Agreement is hereby amended to add a new Schedule III to read in its entirety as set forth on Schedule III attached to this Amendment.

Section 5 Ratification. The Original Agreement is hereby ratified and confirmed and shall remain and continue in full force and effect in accordance with the terms and provisions thereof, as amended by this Amendment, and in the event of any conflict between the Original Agreement and this Amendment, then the terms and conditions of this Amendment shall prevail.

Section 6 Counterparts. This Amendment may be executed in multiple counterparts, each, and together all, of which shall be deemed an original.

Section 7 Joinder of Spouses. The spouses of each individual Owner are joining in the execution of this Amendment to acknowledgment its existence and its provisions, and to evidence the desire to bind their interests in the ownership interests transferred under the Original Agreement, if any, to the performance of this Amendment.

[The remainder of this page is intentionally left blank.]

IN WITNESS WHEREOF, this Amendment has been duly executed by the parties hereto as of the date first above written.

SOP:	XXXXXX OIL PROPERTIES, INC., an Oklahoma corporation
	By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, President
MANAGEMENT:	XXXXXX ENERGY MANAGEMENT, LTD.,a Texas limited partnership
	By:	Xxxxxx Oil Properties, Inc., an Oklahoma corporation, its general partner
	By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, President
XXXXXX LTD.:	XXXXXX ENERGY, LTD., a Texas limited partnership
	By:	Xxxxxx Energy Management, Ltd., a Texas limited partnership, its general partner
		By:	Xxxxxx Oil Properties, Inc., an Oklahoma corporation, its general partner
		By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, President
NEWCO:	XXXXXX ENERGY, INC., a Delaware corporation
	By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, President

S-1

OWNERS OF SOP:			/s/ XXXXX X. XXXXXX Xxxxx X. Xxxxxx
			/s/ XXXXXXXXXXX X. XXXXXX Xxxxxxxxxxx X. Xxxxxx
			/s/ XXXXXXXXX X. XXXXXX Xxxxxxxxx X. Xxxxxx
			/s/ XXXXXX X. XXXXXX Xxxxxx X. Xxxxxx, Trustee of the Xxxxxx X. Xxxxxx Trust u/d/t 3/18/85
			/s/ XXXXXX X. XXXXXX Xxxxxx X. Xxxxxx, Trustee, Xxxxx X. Xxxxxx Children's Trust FBO Xxxxxx X. Xxxxxx
			/s/ XXXXXX X. XXXXXX Xxxxxx X. Xxxxxx, Trustee, Xxxxxx X. Xxxxxx Living Trust
			/s/ ROCKWELL X. XXXXXXXX Rockwell X. Xxxxxxxx
			/s/ XXXXX XXXXXXXX Spouse of Rockwell X. Xxxxxxxx, joining for the limited purposes set forth in Section 7
			/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx
			/s/ XXXXX XXXXX Spouse of Xxxxxxx X. Xxxxx, joining for the limited purposes set forth in Section 7
			/s/ XXXXXX X. XXXXXXXXXX Xxxxxx X. Xxxxxxxxxx
			/s/ XXXXX X. XXXXXXXXXX Spouse of Xxxxxx X. Xxxxxxxxxx, joining for the limited purposes set forth in Section 7
OWNERS OF MANAGEMENT:			/s/ XXXXXX X. XXXXX Xxxxxxx X. Xxxxx

S-2

		/s/ XXXXX X. XXXXX Spouse of Xxxxxxx X. Xxxxx, joining for the limited purposes set forth in Section 7
		/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx
		/s/ XXXXX XXXXX Spouse of Xxxxxxx X. Xxxxx, joining for the limited purposes set forth in Section 7
		XXXXX FAMILY PARTNERSHIP, a Texas partnership
		By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, Partner
		/s/ XXXXXXXXXXX X. XXXXXXX Xxxxxxxxxxx X. Xxxxxxx
		/s/ XXXXXXX X. XXXXXXX Xxxxxxx X. Xxxxxxx
		/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx
		/s/ XXXXXX X. XXXXX Spouse of Xxxxxxx X. Xxxxx, joining for the limited purposes set forth in Section 7
		/s/ G. XXXXXXXXXXX XXXXXX G. Xxxxxxxxxxx Xxxxxx
		/s/ XXXXXXXXX XXXXXX Spouse of G. Xxxxxxxxxxx Xxxxxx, joining for the limited purposes set forth in Section 7
OWNERS OF XXXXXX LTD.:	XXXXXX OIL PROPERTIES, INC., an Oklahoma corporation
	By:	/s/ XXXXXXX X. XXXXX Xxxxxxx X. Xxxxx, President
	/s/ XXXXX X. XXXXXX Xxxxx X. Xxxxxx

S-3

		/s/ XXXXXX X. XXXXXX Xxxxxx X. Xxxxxx, Trustee of the Xxxxxx X. Xxxxxx Trust u/d/t 3/18/85
		/s/ XXXXXXXXXXX X. XXXXXX Xxxxxxxxxxx X. Xxxxxx
		/s/ XXXXXXXXX X. XXXXXX Xxxxxxxxx X. Xxxxxx
			ENCAP ENERGY CAPITAL FUND IV, L.P.
			By: EnCap Equity Fund IV GP, L.P., General Partner of EnCap Energy Capital Fund IV, L.P.
			By: EnCap Investments L.P., General Partner of EnCap Equity Fund IV GP, L.P.
			By: EnCap Investments GP, L.L.C., General Partner of EnCap Investments L.P.
		By:	/s/ XXXXX X. XXXXXX Xxxxx X. Xxxxxx, Senior Managing Director
		ENCAP IV-B ACQUISITIONS, L.P.
			By: EnCap IV-B Acquisitions GP, LLC, General Partner of EnCap IV-B Acquisitions, L.P.
			By: EnCap Energy Capital Fund IV-B, L.P., Sole Member of EnCap IV-B Acquisitions GP, LLC
			By: EnCap Equity Fund IV GP, L.P., General Partner of EnCap Energy Capital Fund IV-B, L.P.
			By: EnCap Investments L.P., General Partner of EnCap Equity Fund IV GP, L.P.
			By: EnCap Investments GP, L.L.C., General Partner of EnCap Investments L.P.
		By:	/s/ XXXXX X. XXXXXX Xxxxx X. Xxxxxx, Senior Managing Director

S-4

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Exhibit 10.6

AMENDMENT TO COMBINATION AGREEMENT
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AMENDMENT TO COMBINATION AGREEMENT

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