<PAGE>

                                                                    EXHIBIT 10.6

                                   AGREEMENT

     THIS AGREEMENT is made this 23rd day of March, 2001, by and between
UNICORP, INC., a Nevada corporation having its principal office and place of
business in Harris County, Texas ("Unicorp"), EQUITABLE ASSETS, INCORPORATED, a
Belize corporation having its principal office and place of business in Belize
City, Belize ("Equitable"), TEXAS NEVADA OIL & GAS CO., a Texas corporation
having its principal office and place of business in Harris County, Texas
("TNOG"), and OPPORTUNITY ACQUISITION COMPANY, a Texas corporation having its
principal office and place of business in Harris County, Texas ("Opportunity").

     WHEREAS, Unicorp desires to spin-off TNOG (the "Spin-Off") to its
shareholders (the "Unicorp Shareholders");

     WHEREAS, following the Spin-Off, and subject to all of the terms of this
Agreement, TNOG will merge with Opportunity; and

     WHEREAS, Equitable, as the controlling shareholder of Unicorp, desires to
ensure that Unicorp and TNOG perform all of their obligations hereunder;

     NOW, THEREFORE, in consideration of the foregoing and the following mutual
covenants and agreements, the parties hereto do hereby agree as follows:

     1.  Spin-Off and Registration.  Unicorp will Spin-Off TNOG to the Unicorp
Shareholders.  The Spin-Off will be accomplished by Unicorp's distribution to
the Unicorp Shareholders all of the issued and outstanding shares of the common
stock, no par value per share, of TNOG (the "TNOG Stock") owned by Unicorp.
Further, the Spin-Off shall be exempt from registration under the Securities Act
of 1933, as amended (the "Securities Act").  In conjunction with the Spin-Off,
TNOG and Unicorp will promptly cause the TNOG Stock to be registered pursuant to
a Registration Statement on Form 10-SB (the "Exchange Act Registration") under
the Securities Exchange Act of 1934, as amended (the "Exchange Act").  After the
Spin-Off and the effectiveness of the Exchange Act Registration, TNOG will be a
fully reporting company under the Exchange Act and will have no liabilities.  In
addition, TNOG will have at least (a) 400 "round lot" shareholders, and (b) one
market maker for the TNOG Stock.

     2.  Merger.  Following the Spin-Off and the effectiveness of the Exchange
Act Registration, Opportunity will enter into an agreement of merger (the
"Merger Agreement") with TNOG, whereby TNOG will merge with Opportunity (the
"Merger") pursuant to Section 368(a)(1)(A) of the Internal Revenue Code of 1986,
as amended. Opportunity will be the surviving entity. The Merger Agreement will
provide that the shares of the common stock of Opportunity (the "Opportunity
Stock") following the Merger will be held five percent by the Unicorp
Shareholders and 95 percent by the shareholders of Opportunity before the
Merger.

     3.  Information Statement.  Prior to the Merger, TNOG and Unicorp will
promptly prepare and send to the Unicorp Shareholders an Information Statement
as required by the Exchange Act (the "Information Statement") in connection with
obtaining approval for the Merger by the Unicorp Shareholders.

     4.  Registration of Opportunity's Stock. In conjunction with the
Information Statement, and as part of the Merger, an S-4 Registration Statement
(the "Securities Act Registration") in accordance with the Securities Act will
be prepared and filed by Opportunity to register the Opportunity Stock to be
received by the Unicorp Shareholders.

     5.  Representations of Unicorp and Equitable.  Unicorp and Equitable
represent that:

        (a) Equitable owns 95.5 percent of the issued and outstanding shares of
     the voting capital stock of Unicorp, and as such, it has the power and
     authority to cause Unicorp and TNOG to perform all of their obligations
     hereunder.

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        (b) Unicorp owns all of the issued and outstanding shares of the capital
     stock of TNOG, and is fully authorized to perform all of its obligations
     hereunder.

     6.  Covenants of Equitable.  Equitable hereby covenants that as the
controlling shareholder of Unicorp and by extension, TNOG, it will cause both
Unicorp and TNOG to perform all of their obligations hereunder, including, but
not limited to, the obligation of Unicorp and TNOG to pay any amounts which may
become due to Opportunity in the event that Unicorp or TNOG fail to satisfy any
of the conditions precedent to Opportunity's obligations hereunder as specified
in Paragraph 7 hereof.

     7.  Conditions Precedent to Opportunity's Obligations.  Notwithstanding
anything herein contained to the contrary, Opportunity shall have no obligation
hereunder with respect to the Merger or any other matter referred to herein, if
any representation by Unicorp or Equitable is untrue, or Unicorp and TNOG shall
fail to consummate the Spin-Off and the Exchange Act Registration within 120
days from the date of this Agreement. Following the Spin-Off and the Exchange
Act Registration, TNOG and Unicorp will enter into the Merger Agreement with
Opportunity. The Merger Agreement will contain the usual and customary
representations and warranties, including, but not limited to a representation
and warranty with respect to the fact that TNOG has no liabilities, and such
other matters as to which the parties can reasonably agree. In addition, the
Merger Agreement will provide for an opinion of counsel by the attorney
representing Unicorp, Equitable, and TNOG that the Spin-Off, the Exchange Act
Registration, and the Merger have been authorized and concluded in conformity
with all applicable laws, including, but not limited to the Securities Act and
the Exchange Act, and any applicable state corporate and securities laws. If
Unicorp, Equitable, or TNOG fail to comply with the terms of this Agreement,
then Opportunity, at its sole option, may terminate this Agreement, whereupon no
party shall have any further obligation hereunder, other than the obligation of
Unicorp, Equitable, and TNOG to repay any of the costs paid by Opportunity as
specified in Paragraph 8 hereof.

     8.  Payment of Unicorp's, Equitable, and TNOG's Expenses.  Opportunity will
pay the costs of Unicorp, Equitable, and TNOG in connection with the Spin-Off,
the Exchange Act Registration, the Merger, and the Information Statement to the
Unicorp Shareholders with respect to the Merger, in an amount not to exceed
$75,000. It is understood by Opportunity that Unicorp, Equitable, and TNOG will
have to pay certain "clean-up costs" pertaining to Unicorp before the
transactions described herein can be completed. However, before payment of any
expenses will be made by Opportunity, any invoices must be submitted by Unicorp
to Opportunity for approval. Thereafter, Opportunity will pay any approved
invoice within 10 days after its receipt and approval by Opportunity. Unicorp,
Equitable, and TNOG will pay all of their costs in excess of $75,000. In the
event that Unicorp, Equitable, or TNOG fail to comply with the terms of this
Agreement, any costs paid by Opportunity on behalf of Unicorp, Equitable, or
TNOG hereunder will be repaid to Opportunity on demand by Opportunity. In
connection with the agreement by Opportunity to pay certain expenses of Unicorp,
Equitable, and TNOG hereunder, Unicorp, Equitable, and TNOG will execute a
promissory note in the form attached hereto as Exhibit A and incorporated herein
by reference for all purposes (the "Note"). If Unicorp, Equitable, and TNOG
fully perform all of their obligations hereunder, the Note will be cancelled.

     9.  Payment of Opportunity's Expenses.  Opportunity will pay all of its own
costs associated with the Merger and the Securities Act Registration, provided
Unicorp, Equitable, and TNOG have performed all of their obligations hereunder.
If Unicorp, Equitable, or TNOG fail to fully perform their obligations
hereunder, then the costs paid by Opportunity associated with the Merger and the
Securities Act Registration, as well as this Agreement, will be added to the
principal of the Note and paid by Unicorp, Equitable, and TNOG.

     10.  Other Agreements and Documents.  In carrying out the intent of this
Agreement, there are several agreements and documents which will need to be
prepared, including, but not limited to the Exchange Act Registration, the
Information Statement, the Securities Act Registration, and the Merger
Agreement.  The parties agree to act in good faith and to attempt to reasonably
agree on the terms of such agreements and documents.

     11.  Attorney's Fees.  In the event that it should become necessary for any
party entitled hereunder to bring suit against any other party to this Agreement
for enforcement of the covenants herein contained, the parties hereby covenant
and agree that the party who is found to be in violation of said covenants shall
also be liable for all reasonable attorney's fees and costs of court incurred by
the other parties hereto.

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     12.  Mediation and Arbitration.  All disputes arising or related to this
Agreement must exclusively be resolved first by mediation with a mediator
selected by the parties, with such mediation to be held in Houston, Texas.  If
such mediation fails, then any such dispute shall be resolved by binding
arbitration under the Commercial Arbitration Rules of the American Arbitration
Association in effect at the time the arbitration proceeding commences, except
that (a) Texas law and the Federal Arbitration Act must govern construction and
effect, (b) the locale of any arbitration must be in Houston, Texas, and (c) the
arbitrator must with the award provide written findings of fact and conclusions
of law.  Any party may seek from a court of competent jurisdiction any
provisional remedy that may be necessary to protect its rights or assets pending
the selection of the arbitrator or the arbitrator's determination of the merits
of the controversy.  The exercise of such arbitration rights by any party will
not preclude the exercise of any self-help remedies (including without
limitation, setoff rights) or the exercise of any non-judicial foreclosure
rights.  An arbitration award may be entered in any court having jurisdiction.

     13.  Benefit.  All the terms and provisions of this Agreement shall be
binding upon and inure to the benefit of and be enforceable by the parties
hereto, and their respective heirs, executors, administrators, personal
representatives, successors and permitted assigns.

     14.  Notices.  All notices, requests, demands, and other communications
hereunder shall be in writing and delivered personally or sent by registered or
certified United States mail, return receipt requested with postage prepaid, if
to Unicorp, Equitable, or TNOG, addressed to Mr. Louis Mehr at 1907 Tarpley,
Katy, Texas 77493, with a copy to M. Stephen Roberts, Esquire, at P.O. Box
981021, Houston, Texas 770098, telecopier (713) 961-1148, and e-mail
sroberts@bigfoot.com; and if to Opportunity, addressed to Mr. John F.
Terwilliger at 801 Travis Street, Suite 1425, Houston, Texas 77002, telecopier
(713) 221-8845, and e-mail mooseoil@swbell.net, with a copy to Norman T.
Reynolds, Esquire, Jackson Walker L.L.P. at 1100 Louisiana Street, Suite 4200,
Houston, Texas 77002, telecopier (713) 752-4221, and e-mail nreynolds@jw.com.
Any party hereto may change its address upon 10 days' written notice to any
other party hereto.

     15.  Construction.  Words of any gender used in this Agreement shall be
held and construed to include any other gender, and words in the singular number
shall be held to include the plural, and vice versa, unless the context requires
otherwise. In addition, the pronouns used in this Agreement shall be understood
and construed to apply whether the party referred to is an individual,
partnership, joint venture, corporation or an individual or individuals doing
business under a firm or trade name, and the masculine, feminine and neuter
pronouns shall each include the other and may be used interchangeably with the
same meaning.

     16.  Waiver.  No course of dealing on the part of any party hereto or its
agents, or any failure or delay by any such party with respect to exercising any
right, power or privilege of such party under this Agreement or any instrument
referred to herein shall operate as a waiver thereof, and any single or partial
exercise of any such right, power or privilege shall not preclude any later
exercise thereof or any exercise of any other right, power or privilege
hereunder or thereunder.

     17.  Cumulative Rights.  The rights and remedies of any party under this
Agreement and the instruments executed or to be executed in connection herewith,
or any of them, shall be cumulative and the exercise or partial exercise of any
such right or remedy shall not preclude the exercise of any other right or
remedy.

     18.  Invalidity.  In the event any one or more of the provisions contained
in this Agreement or in any instrument referred to herein or executed in
connection herewith shall, for any reason, be held to be invalid, illegal or
unenforceable in any respect, such invalidity, illegality, or unenforceability
shall not affect the other provisions of this Agreement or any such other
instrument.

     19.  Time of the Essence.  Time is of the essence of this Agreement.

     20.  Headings.  The headings used in this Agreement are for convenience and
reference only and in no way define, limit, simplify or describe the scope or
intent of this Agreement, and do not effect or constitute a part of this
Agreement.

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<PAGE>

     21.  No Assignment.  This Agreement may not be assigned by any party hereto
without the prior written consent of the other parties hereto.

     22.  Excusable Delay.  None of the parties hereto shall be obligated to
perform and none shall be deemed to be in default hereunder, if the performance
of a non-monetary obligation is prevented by the occurrence of any of the
following, other than as the result of the financial inability of the party
obligated to perform: acts of God, strikes, lock-outs, other industrial
disturbances, acts of a public enemy, wars or war-like action (whether actual,
impending or expected and whether de jure or de facto), arrest or other
restraint of governmental (civil or military) blockades, insurrections, riots,
epidemics, landslides, lightning, earthquakes, fires, hurricanes, storms,
floods, washouts, sink holes, civil disturbances, explosions, breakage or
accident to equipment or machinery, confiscation or seizure by any government of
public authority, nuclear reaction or radiation, radioactive contamination or
other causes, whether of the kind herein enumerated, or otherwise, that are not
reasonably within the control of the party claiming the right to delay
performance on account of such occurrence.

     23.  No Third-Party Beneficiary.  Any agreement to pay an amount and any
assumption of liability herein contained, express or implied, shall be only for
the benefit of the undersigned parties and their respective successors and
permitted assigns (as herein expressly permitted), and such agreements and
assumptions shall not inure to the benefit of the obligees or any other party,
whomsoever, it being the intention of the parties hereto that no one shall be or
be deemed to be a third-party beneficiary of this Agreement.

     24.  Multiple Counterparts.  This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

     25.  Governing law; Jurisdiction.  This Agreement shall be governed by and
construed in accordance with the laws of the State of Texas, without regard to
any conflicts of laws provisions thereof.  Each party hereby irrevocably submits
to the personal jurisdiction of the United States District Court for Harris
County, Texas, as well as of the District Courts of the State of Texas in Harris
County, Texas over any suit, action or proceeding arising out of or relating to
this Agreement.  Each party hereby irrevocably waives, to the fullest extent
permitted by law, any objection which it may now or hereafter have to the laying
of the venue of any such mediation, arbitration, suit, action or proceeding
brought in any such county and any claim that any such mediation, arbitration,
suit, action or proceeding brought in such county has been brought in an
inconvenient forum.

     26.  Perfection of Title.  The parties hereto shall do all other acts and
things that may be reasonably necessary or proper, fully or more fully, to
evidence, complete or perfect this Agreement, and to carry out the intent of
this Agreement.

     27.  Entire Agreement.  This instrument contains the entire understanding
of the parties with respect to the subject matter hereof, and may not be changed
orally, but only by an instrument in writing signed by the party against whom
enforcement of any waiver, change, modification, extension, or discharge is
sought.

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     IN WITNESS WHEREOF, this Agreement has been executed in multiple
counterparts on the date first written above.

                                   UNICORP, INC.



                                   By   /s/ Louis Mehr
                                     ---------------------------------
                                     Louis Mehr, President



                                   EQUITABLE ASSETS, INCORPORATED



                                   By   /s/ Louis Mehr
                                     ---------------------------------
                                     Louis Mehr, President



                                   TEXAS NEVADA OIL & GAS CO.



                                   By   /s/ Louis Mehr
                                     ---------------------------------
                                     Louis Mehr, President



                                   OPPORTUNITY ACQUISITION COMPANY



                                   By   /s/ John F. Terwilliger
                                     ---------------------------------
                                     John F. Terwilliger, President

Attachment:
----------
Exhibit A - The Note

                                       5
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                                  EXHIBIT A

                                PROMISSORY NOTE

$75,000.00                                                     March ___, 2001

     After date, without grace, for value received, UNICORP, INC., a Nevada
corporation having its principal office and place of business in Harris County,
Texas ("Unicorp"), EQUITABLE ASSETS, INCORPORATED, a Belize corporation having
its principal office and place of business in Belize City, Belize ("Equitable"),
and TEXAS NEVADA OIL & GAS CO., a Texas corporation having its principal office
and place of business in Harris County, Texas ("TNOG") (Unicorp, Equitable and
TNOG are collectively referred to herein as the "Makers") hereby jointly and
severally promise to pay to the order of OPPORTUNITY ACQUISITION COMPANY, a
Texas corporation having its principal office and place of business in Harris
County, Texas (the "Payee"), the original principal amount of SEVENTY FIVE
THOUSAND AND NO/100 DOLLARS ($75,000.00), or so much thereof as may actually be
advanced hereunder, together with interest, as hereinafter described.  This Note
is payable in lawful money of the United States of America at 801 Travis, Suite
1425, Houston, Harris County, Texas 77002, or such other place as the Payee may
designate in writing to the Makers.

     The payment of this Note is subject to the terms of that certain Agreement
of even date herewith, between the Makers and the Payee (the "Agreement"), which
is incorporated herein by reference for all purposes.

     This Note shall be due and payable on demand.  Interest at a rate of ten
percent (10%) per annum shall accrue on the unpaid principal balance of this
Note beginning on the date any such funds are advanced to the Makers by the
Payee.  If this Note is not paid at maturity, however maturity may be brought
about, all principal due on the date of such maturity shall bear interest from
the date of such maturity at the maximum contract rate of interest which the
Payee may charge the Makers under applicable law. Interest on the Note shall be
computed for the actual number of days elapsed and on the basis of a year
consisting of 360 days.

     If, for any reason whatever, the interest paid on this Note shall exceed
the maximum non-usurious amount permitted by law, the Payee shall refund to the
Makers such portion of said interest as may be necessary to cause the interest
paid on this Note to equal the maximum non-usurious amount permitted by law, and
no more.  All sums paid or agreed to be paid to the Payee for the use,
forbearance or detention of the indebtedness evidenced hereby shall to the
extent permitted by applicable law be amortized, prorated, allocated and spread
throughout the full term of this Note until payment in full.

     The Makers shall be entitled to prepay this Note in whole or in part at any
time without the payment of a prepayment premium.

     In the event of default in the payment of this Note or under any instrument
executed in connection with this Note, the Makers agree to pay on demand all
costs incurred by the Payee (i) in the collection of any sums, including, but
not limited to, principal, interest, expenses, and reimbursements due and
payable on this Note, and (ii) in the enforcement of the other terms and
provisions of this Note or the Agreement, whether such collection or enforcement
be accomplished by suit or otherwise, including the Payee's reasonable
attorney's fees.

     It is agreed that time is of the essence of this Note, and upon the failure
of the Makers to cure an event of default in the payment of any payment when due
hereunder within 10 days after receipt of notice from the Payee or other holder
of such failure, or upon the failure of the Maker to cure any event of default
within 10 days after receipt of notice from the Payee or other holder of such
failure in the performance of any covenant, agreement or obligation to be
performed under any documents executed in connection with this Note, including,
but not limited to, the Agreement, the Payee may declare the whole sum of the
principal of this Note remaining at the time unpaid, and, to the extent
permitted under applicable law, costs and reasonable attorney's fees incurred by
the Payee in collecting or enforcing the payment thereof, immediately due and
payable without further notice, and failure to exercise said option shall not
constitute a waiver on the part of the Payee of the right to exercise the same
at any other time.

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<PAGE>

     Except as otherwise provided for herein, each maker, surety, guarantor and
endorser of this Note expressly waives all notices, including, but not limited
to, all demands for payment, presentations for payment, notice of opportunity to
cure default, notice of intention to accelerate the maturity, notice of protest
and notice of acceleration of the maturity, notice of protest and notice of
acceleration of the maturity of this Note, and consents that this Note may be
renewed and the time of payment extended without notice and without releasing
any of the parties.

     Any check, draft, money order or other instrument given in payment of all
or any portion of this Note may be accepted by the Payee or any other holder
hereof and handled in collection in the customary manner, but the same shall not
constitute payment hereunder or diminish any rights of the Payee or any other
holder hereof, except to the extent that actual cash proceeds of such instrument
are unconditionally received by the Payee or any other holder hereof and applied
to the indebtedness as herein provided.

     Notwithstanding anything herein contained to the contrary, if any of the
Makers fail to fully perform its obligations under the Agreement or this Note,
then the costs paid by the Payee associated with the Agreement, will be added to
the principal of this Note and paid by the Makers.

     This Note shall be governed by and construed in accordance with the laws of
the State of Texas and applicable federal law.


                                            UNICORP, INC.

                                            By
                                              ---------------------------------
                                              Louis Mehr, President


                                            EQUITABLE ASSETS, INCORPORATED

                                            By
                                              ---------------------------------
                                              Louis Mehr, President


                                            TEXAS NEVADA OIL & GAS CO.

                                            By
                                              ---------------------------------
                                              Louis Mehr, President


                                       2