AMENDMENT TO
CORPORATE GUARANTY
 
This Amendment to Corporate Guaranty (the “Subsidiary Amendment”) is made and
entered into on July 3, 2008, by and between Charles Hill Drilling, Inc. (the
“Guarantor”) and HD Special-Situations, LP (the “Lender”).
 
A. the Guarantor and the Lender have previously entered into a Subsidiary
Guaranty dated May 20, 2008 (the “Guaranty”), in connection with an aggregate of
$1,500,000 in loans from the Lender to Knight Energy Corp. (the “Debtor”).
 
B. Pursuant to Section 3(c) of the Guaranty, the Guarantor and the Lender now
desire to amend the Guaranty as set forth herein in order for it to also apply
to an additional $2,500,000 which is being loaned by the Lender to the Debtor
concurrently herewith.
 
NOW, THEREFORE, in consideration of their respective promises contained herein
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged by the parties, the parties hereby agree as follows:
 
1. Amendment to Recital A. Recital A of the Guaranty is hereby deleted in its
entirety and replaced with the following:

“A. The Lender has advanced an aggregate of $4,000,000 (the “Loan”) to Knight
Energy Corp. (the “Debtor”), to be repaid pursuant to four of the Debtor’s 15%
Senior Secured Promissory Notes (individually, a “Note;” collectively, the
“Notes”).”

2. Amended Reference to Certain Documents. All references in the Guaranty to
“Security Agreement,” “Guaranty” and “Deed of Trust, Security Agreement,
Assignment of Production and Financing Statement” shall include all amendments
to those documents.

3. Ratification of Remaining Terms. Except as expressly set forth in this
Amendment, all of the terms and provisions of the Guaranty shall remain in full
force and effect.

IN WITNESS WHEREOF, the parties hereto have caused this Subsidiary Amendment to
be duly executed by their respective authorized persons on the date first
written above.
 

 
CHARLES HILL DRILLING, INC.
     
By:
   
Title:
         
By:
   
Title:
 

 
 

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HD SPECIAL-SITUATIONS, LP
     
By:
   
Title:
 

 
 
 

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