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                           P R 0 M I S S 0 R Y  N 0 T E
                           ----------------------------


$250,000.00                     AMBLER, PENNSYLVANIA           FEBRUARY 11, 2002

         FOR VALUE RECEIVED, REGENT ENERGY CORPORATION, ("Maker", whether one or
more), promises to pay to the order of ENERGY INVESTORS, LLC, in Ambler,
Pennsylvania, the sum of TWO HUNDRED FIFTY THOUSAND AND NO/100 DOLLARS
($250,000.00) in lawful money of the United States of America which shall be
legal tender in payment of all debts and dues, public and private, at the time
of payment, and to pay interest on the unpaid principal balance of this
promissory note (the "Note") from time to time outstanding from the date hereof
until maturity at a per annum rate of interest equal to the lesser of (i) the
"Applicable Rate" or (ii) the "Maximum Rate", as those terms are herein defined;

         (i)      The term "Applicable Rate" means TWELVE PERCENT (12%) interest
                  per annum.

         (ii)     The term "Maximum Rate" means the maximum lawful rate of
                  interest permitted to be charged by the holder of this Note to
                  Maker, as a corporation, under the law of the State of
                  Pennsylvania and the United States of America.

         Interest shall be computed on a per annum basis of a year of 365 or 366
days, as the case may be.

         This Note shall be for a term of thirty (30) days from the date hereof.
If not sooner paid, the full principal amount, plus all accrued interest, shall
be payable upon maturity to the holder of this Note at 230 Mathers Road, Ambler,
Pennsylvania, or at such other address as may be provided in writing to Maker.

         This Note may be prepaid in whole or in part at any time and from time
to time without prepayment charge or penalty. Simultaneously with any prepayment
of principal, there must also be paid all interest accrued on the amount of
principal so prepaid and all other sums then due hereunder or under any
instrument, document, or other writing now or hereafter securing or pertaining
to this Note.

         Maker further agrees that all past due principal and accrued interest
shall bear interest from the date it is due until paid at the Maximum Rate; and
if no Maximum Rate is applicable, then at the rate of eighteen percent (18.00%)
per annum; provided, however, nothing herein or in any instrument, document, or
other writing now or hereafter securing this Note shall entitle the holder of
this Note to contract for, charge, receive, take, or reserve interest hereon in
excess of the Maximum Rate. In the event this Note is prepaid in full or in the
event the maturity of this Note is accelerated prior to the end of the full
stated term hereof, and the interest received prior to such prepayment or
acceleration exceeds interest calculated at the Maximum Rate, the then holder of
this Note shall credit the amount of such excess against the amounts lawfully
owing under this Note or under any instrument, document, or other writing
securing this Note as of the date of such prepayment or acceleration, in any
order, preference, or manner as the holder hereof may elect, until all sums
lawfully owing to the holder hereof are fully and finally paid, and the balance,
if any, shall be refunded to the person or entity entitled thereto.

         Maker further agrees that, notwithstanding any other provision of this
Note, in no event shall the aggregate of (i) all interest which has accrued on
this Note from the date hereof through the date of such calculation, and (ii)
the sum of all other amounts accrued or paid which, under applicable laws, are
considered interest from the date hereof through the date of such calculation,
ever exceed interest calculated at the


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Maximum Rate on the principal balance of this Note from time to time remaining
unpaid. In this connection, it is agreed that in the execution, delivery, and
acceptance of this Note, Maker and the holder of this Note intend to contract in
strict compliance with applicable state and federal laws from time to time in
effect. In furtherance thereof, none of the terms of this Note or of any
instrument, document, or other writing now or hereafter securing or pertaining
to this Note shall ever be construed to create a contract to pay for the use,
forbearance, or detention of money any interest at a rate in excess of the
Maximum Rate. No person or entity shall ever be liable for interest in excess of
the Maximum Rate, and the provisions of this paragraph shall control over all
other provisions of this Note or the Security Documents (hereafter defined)
which may be in apparent conflict therewith. Specifically, and without limiting
the generality of the foregoing, Maker agrees that:

         (i)      if, under any circumstances, the aggregate amounts paid on
                  this Note prior to and incident to final payment hereof
                  include amounts which by law are considered interest which
                  would exceed the Maximum Rate, Maker agrees that such payment
                  and collection will have been and will be deemed to have been
                  the result of mathematical error on the part both of Maker and
                  the holder of this Note, and the recipient of such excess
                  payments shall promptly refund the amount of such excess (to
                  the extent only of such interest payments above the maximum
                  amount which could lawfully have been collected and retained)
                  upon discovery of such error by the recipient of such payment
                  or upon receipt of notice thereof from the person or entity
                  making such payment; and

         (ii)     to the fullest extent permitted by applicable law, all sums
                  paid or agreed to be paid to the holder hereof for the use,
                  forbearance, or detention of the indebtedness evidenced hereby
                  shall be amortized, prorated, allocated, and spread throughout
                  the full term of this Note.

         Maker further agrees that if any default occurs in the payment of this
Note, principal or interest, or in the payment of any other note or indebtedness
of Maker, Maker's successors or assigns, to the then holder of this Note, or
upon the occurrence of any default under any of the Security Documents, or under
any other instrument, document, or other writing then securing this Note or any
other indebtedness of Maker, Maker's successors or assigns, to the then holder
of this Note, then, in any such event, and at any time thereafter, cumulative of
and in addition to all other rights and remedies available to the holder of this
Note, at the option of such holder, the entire unpaid principal balance and all
accrued interest then owing on this Note shall immediately mature and be due and
payable.

         Maker further agrees that if the original or a copy of this Note is
placed in the hands of an attorney for collection after the occurrence of any
default hereunder, or for the purpose of being sued upon or established in any
manner in any court, or for any other purpose whatsoever in any manner connected
with or pertaining to (i) the extension of credit evidenced hereby, (ii) Maker,
Maker's successors or assigns, or (iii) any property, rights, or interests now
or hereafter securing this Note, then, in any such event, Maker promises to pay
to the then holder of this Note all reasonable attorneys' fees, costs, and
expenses theretofore, then, and thereafter paid or incurred by any holder of
this Note in any manner connected therewith.

         To the maximum extent not prohibited by applicable law, Maker, on
behalf of Maker and Maker's successors and assigns, hereby (i) waives grace,
demand, notice of default, notice of intent to accelerate maturity, notice that
the holder hereof will not or will no longer accept late payments, notice of
acceleration of maturity, presentment for acceleration, presentment for payment,
protest, notice of protest and of dishonor, and diligence in taking any action
with respect to any security or the collection of any sums owing hereon and (ii)
consents to any and all renewals, extensions, modifications, and rearrangements
hereof and to the release of all or any part of the security herefor or any
person or entity liable hereon or herefor under any terms deemed by the holder
hereof, in its sole discretion, to be adequate. Any such renewal, extension,
modification, or


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rearrangement, or the release of any such security, person, or entity, may be
made without notice to Maker, Maker's successors or assigns, and without
affecting any security herefor or the liabilities and obligations of Maker,
Maker's successors or assigns, which are not expressly released in writing.
Maker further agrees that the exercise of any right or remedy conferred upon any
holder hereof in this Note, or in any instrument, document, or other writing now
or hereafter securing or otherwise pertaining to this Note, or securing or
pertaining to any other indebtedness now or hereafter owing by Maker to any
holder hereof, shall be wholly discretionary with the holder of this Note, and
the exercise of, or failure to exercise, any such right or remedy shall not in
any manner affect, impair, or diminish the obligations and liabilities of Maker,
or constitute or be deemed a waiver of any such right or remedy or any other
past, present, or future right or remedy of any holder hereof. Maker further
agrees that (without limiting the foregoing) the acceptance of late payments or
the failure to exercise the option to accelerate the maturity of this Note upon
any default hereunder shall not in any manner constitute a waiver of the right
to exercise the option to accelerate the maturity of this Note upon the failure
to promptly pay any subsequent payment or in the event there exists or
thereafter occurs any other or subsequent default, and no waiver shall be
enforceable against the holder of this Note unless such waiver is expressly set
forth in writing and duly executed by such holder.

         WITHOUT LIMITATION OF ANY OTHER PROVISION HEREIN, THE MAKER HEREBY
EMPOWERS ANY ATTORNEY OR ANY COURT OF RECORD, AFTER THE OCCURRENCE OF ANY EVENT
OF DEFAULT HEREUNDER, TO APPEAR FOR THE MAKER AND, WITH OR WITHOUT COMPLAINT
FILED, CONFESS JUDGMENT, OR A SERIES OF JUDGMENTS, AGAINST THE MAKER IN FAVOR OF
THE HOLDER OF THIS NOTE FOR ALL AMOUNTS DUE HEREUNDER AND ALL ACCRUED INTEREST,
TOGETHER WITH COSTS OF SUIT AND AN ATTORNEY'S COMMISSION OF THE GREATER OF 10%
OF SUCH PRINCIPAL AND INTEREST OR $1,000 ADDED AS A REASONABLE ATTORNEY'S FEE
AND FOR DOING SO THIS NOTE OR A COPY VERIFIED BY AFFIDAVIT SHALL BE A SUFFICIENT
WARRANT. THE MAKER HEREBY FOREVER WAIVES AND RELEASES ALL ERRORS IN SAID
PROCEEDINGS AND ALL RIGHTS OF APPEAL AND ALL RELIEF FROM ANY AND ALL
APPRAISEMENT, STAY OR EXEMPTION LAWS OF ANY STATE NOW IN FORCE OR HEREAFTER
ENACTED. NO SINGLE EXERCISE OF THE FOREGOING POWER TO CONFESS JUDGMENT, OR A
SERIES OF JUDGMENTS, SHALL BE DEEMED TO EXHAUST THE POWER, WHETHER OR NOT ANY
SUCH EXERCISE SHALL BE HELD BY ANY COURT TO BE INVALID, VOIDABLE, OR VOID, BUT
THE POWER SHALL CONTINUE UNDIMINISHED AND IT MAY BE EXERCISED FROM TIME TO TIME
AS OFTEN AS THE HOLDER OF THIS NOTE SHALL ELECT UNTIL SUCH TIME AS THE HOLDER OF
THIS NOTE SHALL HAVE RECEIVED PAYMENT IN FULL OR ALL AMOUNTS PAYABLE BY MAKER.

         This Note, and all instruments, documents, and other writings
evidencing, securing, or pertaining to the indebtedness evidenced hereby have
been executed in Harris County, Texas, and shall be construed in accordance with
and governed by the applicable laws of the United States of America and the
State of Pennsylvania. Maker further agrees and consents to all of the
provisions of the Security Documents and of all other instruments, documents,
and other writings now or hereafter securing or pertaining to this Note and
agrees that all of same are binding on Maker, and on the heirs, successors,
legal representatives, and assigns of Maker.

         To the maximum extent not prohibited by applicable law, this Note is
secured by all security instruments, collateral assignments, mortgages, liens,
and lien instruments (the "Security Documents") executed by Maker (or by any
other person or entity) in favor of the holder of this Note, including those
executed simultaneously herewith, those executed heretofore, and those hereafter
executed, including, without limitation: that certain Deed of Trust and Security
Agreement (the "Deed of Trust") dated effective August 15, 2001, executed by
Maker to Donald G. Sinex, Trustee, which Deed of Trust is recorded in Book 1327,
Page 212, records of San Juan County, New Mexico; Uniform Commercial Code
Financing Statement also dated effective August 15, 2001 and recorded in UCC
file No. 2001082006524, Office of the Secretary of State of New Mexico; Renewal
and Extension of Lien, dated November 27, 2001, executed by Maker and Energy
Investors, LLC, and recorded in Book 1334, Page 367, records of San Juan County,
New Mexico; and together with the Amendment, Renewal and Extension of Lien
executed by Maker of even date herewith. All of the foregoing documents describe
or reference Mortgaged Properties in the Horshoe-Gallup Unit on Exhibit "A"
attached thereto, reference to which is here made for all purposes.


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         THE MAKER IRREVOCABLY WAIVES ANY AND ALL RIGHT THE MAKER MAY HAVE TO A
TRIAL BY JURY IN ANY ACTION, PROCEEDING OR CLAIM OF ANY NATURE RELATING TO THIS
NOTE, ANY DOCUMENTS EXECUTED IN CONNECTION WITH THIS NOTE OR ANY TRANSACTION
CONTEMPLATED IN ANY OF SUCH DOCUMENTS. THE MAKER ACKNOWLEDGES THAT THE FOREGOING
WAIVER IS KNOWING AND VOLUNTARY.

         The Maker acknowledges that it has read and understood all the
provisions of this Note, including the confession of judgment and waiver of jury
trial, and has been advised by counsel as necessary or appropriate.

         Notwithstanding any provision of this Promissory Note to the contrary,
the Holder of this Promissory Note acknowledges that the obligations imposed on
Maker by this Promissory Note, and the rights of any and all holders hereof, are
subject to and subordinate to the Mortgage, Assignment of Production, Security
Agreement and Financing Statement as described in Section VII (p) of the Deed of
Trust as amended, renewed and extended that secures the obligations under this
Promissory Note.

                                        REGENT ENERGY CORPORATION



                                        By
                                          --------------------------------------
                                            John N. Ehrman , President



                                                                  Initialed for
                                                                 Identification:

                                                                 ---------------


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