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                                                                   EXHIBIT 10.25

                       FIRST AMENDMENT TO CREDIT AGREEMENT

         THIS FIRST AMENDMENT TO CREDIT AGREEMENT (hereinafter referred to as
the "First Amendment") executed as of the 26th day of April, 2001, by and
between ADDISON ENERGY INC. ("Borrower") and BANK ONE CANADA ("Bank One"), and
each of the financial institutions which is a party hereto (as evidenced by the
signature pages to this Agreement) or which may from time to time become a party
hereto pursuant to the provisions of Section 28 of the Credit Agreement (as
hereinafter defined) or any successor or assignee thereof (hereinafter
collectively referred to as "Lenders", and individually, "Lender") and Bank One,
as Administrative Agent (the "Agent").

                                   WITNESSETH:

         WHEREAS, as of April 26, 2001, EXCO Resources Canada Inc. ("EXCO"), the
Lenders and the Agent entered into a Credit Agreement pursuant to which the
Lenders made available to the Borrower a revolving credit facility of up to
$77,500,000 Canadian (the "Credit Agreement"); and

         WHEREAS, immediately after the Effective Date of the Credit Agreement
EXCO and Borrower were amalgamated under the name of Addison Energy Inc.;

         WHEREAS, the Borrower, the Lenders and the Agent wish to amend the
Credit Agreement to confirm the Borrower is bound by the obligations of EXCO
under the Credit Agreement.

         NOW, THEREFORE, the parties agree to amend the Credit Agreement as
follows:

         1. Unless otherwise defined herein all defined terms used herein shall
have the same meaning as ascribed to such terms in the Credit Agreement.

         2. Any and all references in the Credit Agreement to EXCO Resources
Canada Inc. are deleted and the name Addison Energy Inc. is substituted in lieu
thereof

         3. Borrower hereby confirms to the Lenders and the Agent that it is
bound by all of the obligations of EXCO under the Credit Agreement. Borrower
further confirms that the property of EXCO and the property of Borrower
immediately prior to their amalgamation to form Addison Energy Inc. continues to
be the property of Borrower and Borrower continues to be liable for the
obligations of each of EXCO and pre-amalgamation Addison Energy Inc. existing
immediately prior to their amalgamation to form Borrower including such
obligations of EXCO under the Credit Agreement.

         4. Except to the extent its provisions are specifically amended,
modified or superseded by this First Amendment, the representations, warranties
and affirmative and negative covenants of the Borrower contained in the Credit
Agreement are incorporated herein by reference for all purposes as if copied
herein in full. The Borrower hereby restates and reaffirms each and every term
and provision of the Credit Agreement, as amended, including, without
limitation, all representations, warranties and affirmative and negative
covenants.

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Except to the extent its provisions are specifically amended, modified or
superseded by this First Amendment, the Credit Agreement, as amended, and all
terms and provisions thereof shall remain in full force and effect, and the same
in all respects are confirmed and approved by the Borrower and the Lenders.

         5. This First Amendment shall be effective as of the date first above
written, but only upon the satisfaction of the conditions precedent set forth in
Paragraph 6 hereof (the "First Amendment Effective Date").

         6. The obligations of Lenders under this First Amendment shall be
subject to the following conditions precedent:

                  (a) Execution and Delivery. The Borrower shall have executed
         and delivered this First Amendment, all in form and substance
         satisfactory to the Agent;

                  (b) Representations and Warranties. The representations and
         warranties of the Borrower under this First Amendment are true and
         correct in all material respects as of the date (except to the extent
         that such representations and warranties relate solely to an earlier
         date);

                  (c) No Event of Default. No Event of Default shall have
         occurred and be continuing nor shall any event have occurred or failed
         to occur which, with the passage of time or service of notice, or both,
         would constitute an Event of Default;

                  (d) Other Documents. The Agent shall have received such other
         instruments and documents incidental and appropriate to the transaction
         provided for herein as the Agent or its counsel may reasonably request,
         and all such documents shall be in form and substance satisfactory to
         the Agent;

                  (e) Legal Matters Satisfactory. All legal matters incident to
         the consummation of the transactions contemplated hereby shall be
         reasonably satisfactory to special counsel for the Agent retained at
         the expense of Borrower.

         7. Borrower hereby represents and warrants that all factual information
heretofore and contemporaneously furnished by or on behalf of Borrower to Agent
for purposes of or in connection with this First Amendment does not contain any
untrue statement of a material fact or omit to state any material fact necessary
to keep the statements contained herein or therein from being misleading. Each
of the foregoing representations and warranties shall constitute a
representation and warranty of Borrower made under the Credit Agreement, and it
shall be an Event of Default if any such representation and warranty shall prove
to have been incorrect or false in any material respect at the time given. Each
of the representations and warranties made under the Credit Agreement (including
those made herein) shall survive and not be waived by the execution and delivery
of this First Amendment or any investigation by Lenders.


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         8. This First Amendment may be executed in any number of counterparts
and all of such counterparts taken together shall be deemed to constitute one
and the same instrument.

         9. This First Amendment shall be governed by and construed in
accordance with the laws of the Province of Alberta, Canada.

         10. WRITTEN CREDIT AGREEMENT. THE CREDIT AGREEMENT, AS AMENDED BY THIS
FIRST AMENDMENT REPRESENTS THE FINAL AGREEMENT BETWEEN AND AMONG THE PARTIES AND
MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN AND
AMONG THE PARTIES.

         IN WITNESS WHEREOF, the parties have caused this First Amendment to
Credit Agreement to be duly executed as of the date first above written.

                                    BORROWER:

                                    ADDISON ENERGY INC.



                                    By: /s/ RICHARD E. MILLER
                                       -----------------------------------------
                                             Richard E. Miller, Vice President

                                    LENDERS:

                                    BANK ONE CANADA



                                    By: /s/ MICHAEL N. TAM
                                       -----------------------------------------
                                             Michael N. Tam, Vice President


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                                    BNP PARIBAS (CANADA)



                                    By: /s/ MICHAEL GOSSELIN
                                       ----------------------------------------
                                             Michael Gosselin, Director
                                             Energy & Project Finance



                                    By: /s/ PAUL MCCUAIL
                                       ----------------------------------------
                                             Paul McCuail, Vice President

                                    COMERICA BANK-CANADA



                                    By: /s/ ROBERT C. ROSEN
                                       ----------------------------------------
                                             Robert C. Rosen, Vice President


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                                    ADMINISTRATIVE AGENT:

                                    BANK ONE CANADA



                                    By: /s/ MICHAEL N. TAM
                                       ----------------------------------------
                                             Michael N. Tam, Vice President

                                    DOCUMENTATION AGENT:

                                    BNP PARIBAS (CANADA)



                                    By: /s/ MICHAEL GOSSELIN
                                       ----------------------------------------
                                             Michael Gosselin, Director
                                             Energy & Project Finance



                                    By: /s/ PAUL MCCUAIL
                                       ----------------------------------------
                                             Paul McCuail, Vice President


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