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                                                            EXHIBIT 10.6

                                    GUARANTY

         This Guaranty is made as of the 18th day of January 2000, by CONCORDE
GAMING CORPORATION, (the "Guarantor") a Colorado corporation, for the benefit of
the National City Bank of Evansville (the "Lender").

         Bayfront Ventures, a Florida general partnership (the "Borrower"), and
the Lender have entered into a Loan Agreement of even date herewith (together
with all amendments, modifications and restatements of such Agreement, the "Loan
Agreement") setting forth the terms on which the Lender will make certain
advances to the Borrower, the proceeds of which will be used by the Borrower for
the Borrower's general business purposes.

         As a condition to making advances under the Loan Agreement, the Lender
has required the execution and delivery of this Guaranty.

         The Guarantor indirectly owns an 80% interest in the Borrower and
accordingly expects to receive direct economic benefits from the advances under
the Loan Agreement.

         ACCORDINGLY, the Guarantor, in consideration of the premises and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, hereby agrees as follows:

         1. All terms defined in the Loan Agreement that are not otherwise
defined herein shall have the meanings given them in the Loan Agreement.

         2. The Guarantor hereby absolutely and unconditionally guarantees to
the Lender the full and prompt payment when due, whether at maturity or earlier
by reason of acceleration or otherwise, of the Obligations.

         3. The Guarantor will pay all reasonable costs, expenses and attorneys'
fees paid or incurred by the Lender in endeavoring to collect the Obligations
and in enforcing this Guaranty.

         4. No act or thing need occur to establish the liability of the
Guarantor hereunder, and with the exception of full payment, no act or thing
(including, but not limited to, a discharge in bankruptcy of the Obligations,
and/or the running of the statute of limitations) relating to the Obligations
which but for this provision could act as a release of the liabilities of the
Guarantor hereunder, shall in any way exonerate the Guarantor, or affect,
impair, reduce or release this Guaranty and the liability of the Guarantor
hereunder; and this shall be a continuing, absolute and unconditional guaranty
and shall be in force and be binding upon the Guarantor until the Obligations
are fully paid.
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         5. The liability of the Guarantor hereunder shall not be affected or
impaired in any way by any of the following acts or things (which the Lender is
hereby expressly authorized to do, omit or suffer from time to time without
notice to or consent of anyone): (i) any acceptance of collateral security,
guarantors, accommodation parties or sureties for any or all Obligations; (ii)
any extensions or renewal of any Obligations (whether or not for longer than the
original period) or any modification of the interest rate, maturity or other
terms of any Obligations; (iii) any waiver or indulgence granted to the
Borrower, any delay or lack of diligence in the enforcement of any Obligations;
(iv) any full or partial release of, compromise or settlement with, or agreement
not to sue, the Borrower or any other guarantor or other person liable on any
Obligations; (v) any release, surrender, cancellation or other discharge of any
Obligations or the acceptance of any instrument in renewal or substitution for
any instrument evidencing Obligations; (vi) any failure to obtain collateral
security (including rights of setoff) for any Obligations, or to see to the
proper or sufficient creation and perfection thereof, or to establish the
priority thereof, or to preserve, protect, insure, care for, exercise or enforce
any collateral security for any of the Obligations; (vii) any modification,
alteration, substitution, exchange, surrender, cancellation, termination,
release or other change, impairment, limitation, loss or discharge of any
collateral security for any of the Obligations; (viii) any assignment, sale,
pledge or other transfer of any of the Obligations; or (ix) any manner, order or
method of application of any payments or credits on any Obligations. The
Guarantor waives any and all defenses and discharges available to a surety,
guarantor, or accommodation co-obligor, dependent on its character as such.

         6. The Guarantor waives any and all defenses, claims, setoffs and
discharges of the Borrower, or any other obligor, pertaining to the Obligations,
except the defense of discharge by payment in full. Without limiting the
generality of the foregoing, the Guarantor will not assert against the Lender
any defense of waiver, release, discharge in bankruptcy, statute of limitations,
res judicata, statute of frauds, anti-deficiency statute, fraud, ultra vires
acts, usury, illegality or unenforceability which may be available to the
Borrower in respect of the Obligations, or any setoff available against the
Lender to the Borrower, whether or not on account of a related transaction, and
the Guarantor expressly agrees that it shall be and remain liable for any
deficiency remaining after foreclosure of any security interest securing any
Obligations, notwithstanding provisions of law that may prevent the Lender from
enforcing such deficiency against the Borrower. The liability of the Guarantor
shall not be affected or impaired by any voluntary or involuntary liquidation,
dissolution, sale or other disposition of all or substantially all the assets,
marshaling of assets and liabilities, receivership, insolvency, bankruptcy,
assignment for the benefit of creditors, reorganization, arrangement,
composition or readjustment of, or other similar event or proceeding affecting,
the Borrower or any of the Borrower's assets. The Guarantor will not assert
against the Lender any claim, defense or setoff available to the Guarantor
against the Borrower.

         7. The Guarantor also hereby waives: (i) presentment, demand for
payment, notice of dishonor or nonpayment, and protest of the Obligations; (ii)
notice of the acceptance hereof by the Lender and of the creation and existence
of all Obligations; and

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(iii) notice of any amendment to or modification of any of the terms and
provisions of the Loan Documents. The Lender shall not be required to first
resort for payment of the Obligations to the Borrower or any other persons or
corporations, their properties or estates, or to any collateral, property, liens
or other rights or remedies whatsoever.

         8. Whenever, at any time or from time to time, the Guarantor shall make
any payment to the Lender hereunder, the Guarantor shall notify the Lender in
writing that such payment is made under this Guaranty for such purpose. If any
payment applied by the Lender to the Obligations is thereafter set aside,
recovered, rescinded or required to be returned for any reason (including,
without limitation, the bankruptcy, insolvency or reorganization of the Borrower
or any other obligor), the Obligations to which such payment was applied shall
for the purposes of this Guaranty be deemed to have continued in existence,
notwithstanding such application, and this Guaranty shall be enforceable as to
such Obligations as fully as if such application had never been made.

         9. No payment by the Guarantor pursuant to any provision hereof shall
entitle the Guarantor, by subrogation to the rights of the Lender or otherwise,
to any payment by the Borrower or out of the property of the Borrower until all
of the Obligations (including interest) and all reasonable costs, expenses and
attorneys' fees paid or incurred by the Lender in endeavoring to collect the
Obligations and enforcing this Guaranty have been fully paid. The Guarantor will
not exercise or enforce any right of contribution, reimbursement, recourse or
subrogation available to the Guarantor as to any Obligations, or against any
person liable therefor, or as to any collateral security therefor, unless and
until all such Obligations shall have been fully paid and discharged.

         10. This Guaranty shall constitute a continuing and irrevocable
Guaranty, and the Lender may continue, without notice to or consent by the
Guarantor, to make loans and extend other credit or financial accommodation to
or for the account of the Borrower in reliance upon this Guaranty until written
notice of revocation of this Guaranty shall have been received by the Lender
from the Guarantor. Any such notice of revocation shall not affect this Guaranty
in relation to any Obligations then existing or created thereafter pursuant to
any previous commitment of the Lender to the Borrower, or any extensions or
renewals of any such Obligations, and as to all such Obligations and extensions
or renewals thereof, this Guaranty shall continue effective until the same have
been fully paid with interest.

         11. This Guaranty shall be binding upon the successors and assigns of
the Guarantor, and shall inure to the benefit of the successors and assigns of
the Lender.

         12. The Guarantor irrevocably (i) agrees that any suit, action or other
legal proceeding arising out of or relating to this Guaranty may be brought in a
court of record in the State of Indiana or in the Courts of the United States
located in such State, (ii) consents to the jurisdiction of each such court in
any suit, action or proceeding, (iii) waives any objection which it may have to
the laying of venue of any such suit, action or proceeding in any such

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courts and any claim that any such suit, action or proceeding has been brought
in an inconvenient forum, and (iv) agrees that a final judgment in any such
suit, action or proceeding shall be conclusive and may be enforced in other
jurisdictions by suit on the judgment or in any other manner provided by law.

         13. THE GUARANTOR HEREBY IRREVOCABLY WAIVES ALL RIGHTS TO TRIAL BY JURY
IN ANY ACTION, PROCEEDING OR COUNTERCLAIM ARISING OUT OF, BASED ON OR PERTAINING
TO THIS GUARANTY OR ANY OTHER RELATED LOAN DOCUMENT TO WHICH THE GUARANTOR IS A
PARTY.

         14. The Guarantor hereby covenants with and for the benefit of the
Lender that the Guarantor will provide copies of its 10K and 10Q reports to the
Lender within five business days of their filing with the SEC.

         IN WITNESS WHEREOF, the Guarantor has executed this Guaranty as of the
day and year first above written.

                                                     CONCORDE GAMING CORPORATION

                                                     By
                                                      --------------------------

                                                       Its
                                                          ----------------------

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                                                                     EXHIBIT 4.3

                            CERTIFICATE OF AMENDMENT
                            ------------------------

          Pursuant to Section 27 of the Rights Agreement between Sun Company,
     Inc. (the "Company") and First Chicago Trust Company of New York, as Rights
     Agent (the "Rights Agent"), dated as of February 1, 1996, and last amended
     as of July 3, 1997 (the "Rights Agreement"), Sunoco, Inc., the successor by
     name change to the Company HEREBY CERTIFIES THAT:

          the Second Amendment to the Rights Agreement, attached hereto, is in
          compliance with the terms of said Section 27 of the Rights Agreement,
          as amended.

     Dated as of February 3, 2000.

                                         SUNOCO, INC.

                                         By:  /s/ THOMAS W. HOFMANN
                                              -----------------------
                                              Thomas W. Hofmann
                                              Vice President and
                                              Chief Financial Officer

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