<PAGE>

                                                                     Exhibit 4.2

                UNCONDITIONAL MINIMUM PAYMENT GUARANTY AGREEMENT
                      FOR FISCAL YEAR ENDING MARCH 31, 2001

         THIS UNCONDITIONAL MINIMUM PAYMENT GUARANTY AGREEMENT for Fiscal Year
ending March 31, 2001 (the "Guaranty") is entered into as of March 31, 2000, by
HARRAH'S ENTERTAINMENT, INC., a Delaware corporation, and HARRAH'S OPERATING
COMPANY, INC., a Delaware corporation (each a "Guarantor" and collectively the
"Guarantors") in favor of the STATE OF LOUISIANA by and through the LOUISIANA
GAMING CONTROL BOARD (the "LGCB").

                                    RECITALS

         A. That certain Casino Operating Contract (the "COC") between Jazz
Casino Company, L.L.C., a Louisiana limited liability company (the "Company"),
and the LGCB, dated as of October 30, 1998, sets forth the conditions,
covenants, obligations, requirements and terms pursuant to which the Company has
the authority to conduct gaming operations at the Casino.

         B. As used in this Guaranty, all capitalized terms used herein but not
defined herein shall be used herein as defined in the COC.

         C. The Company has caused this Guaranty to be provided to the LGCB for
Fiscal Year ending March 31, 2001 (the "Covered


<PAGE>

Fiscal Year"), as required by the COC.

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the foregoing and other benefits
accruing to the Guarantors, the receipt and sufficiency of which are hereby
acknowledged, the Guarantors hereby solidarily make the following
representations and warranties to the LGCB, and hereby solidarily covenant and
agree for the benefit of the LGCB as follows:

1.             Obligations Guaranteed and Method of Drawing.

1.1            The Guarantors hereby irrevocably, unconditionally, and in solido
with each other and with the Company, guarantee for the Covered Fiscal Year:

         (a) the full, complete and timely payment and performance of all of the
Minimum Payment obligations of the Company to the LGCB under and in accordance
with the provisions of the COC; and

         (b) the full, complete and timely payment to the LGCB of all of the
Daily Payments, Required Payments and Minimum Payment in accordance with the
provisions of the COC.

1.2            If there is any delay in timely paying to the LGCB any and/or all
of the Daily Payments, Required Payments and/or Minimum Payment as and when
required under the COC for the



                                       2
<PAGE>

Covered Fiscal Year, the Guarantors shall also pay to the LGCB interest on such
payments due at the Default Interest Rate (as provided in Section 6.7 of the
COC) from the date each payment was due, until paid to the LGCB.

1.3            In no event shall the aggregate total of Daily Payments, Required
Payments and the Minimum Payment to the LGCB under this Guaranty for the Covered
Fiscal Year exceed ONE HUNDRED MILLION DOLLARS ($100,000,000.00), plus, and in
addition thereto, any interest and attorneys' fees applicable to the Guaranty
Obligation provided for in the COC or in this Guaranty.

1.4            If the LGCB has not been timely paid any one or more of the
required Daily Payments for the Covered Fiscal Year, then (a) the LGCB may make
drawings under this Guaranty by providing written notice to the Guarantors that
one or more of the required Daily Payments have not been timely paid and the
principal amount of such Daily Payments then due (the "Notice of Drawing"), and
(b) the Guarantors shall pay to the LGCB all required but unpaid Daily Payments,
plus interest at the Default Interest Rate, upon receipt of the Notice of
Drawing. Guarantors shall make payment by wire or other electronic transfer as
provided in the Notice of Drawing, on or before the time the Daily Payments are
due under Section 6.5 - "Daily Deposits" of the COC.

1.5            The Guarantors shall not be obligated to make any



                                       3
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Daily Payments due for any day which is twenty (20) days or more prior to the
LGCB giving the Notice of Drawing; provided however, that any payments which are
suspended pursuant to Section 6.3(a) of the COC shall not be due and payable
until the period of the suspension has expired.

1.6            Once a Minimum Payment Default has occurred and a Notice of
Drawing has been provided to the Guarantors, the Guarantors shall be obligated
without any further notice by the LGCB to pay, and will pay, to the LGCB any
required Daily Payments for the Covered Fiscal Year on a daily basis for the
remainder of the Covered Fiscal Year (in which a Minimum Payment Default occurs)
to the extent such Daily Payments have not been timely paid.

1.7            In no event shall the Guarantors be liable to the LGCB under this
Guaranty for any amount in excess of the difference between the Minimum Payment
for the Covered Fiscal Year and the total of the Louisiana Gross Gaming Revenue
Share Payments which have been paid to the LGCB for said Fiscal Year or liable
for any Daily Payments due for and in any Fiscal Year following the Covered
Fiscal Year.

1.8            All of the obligations undertaken hereinabove by the Guarantors
in this Section 1 and any amounts which may be due under Section 6.2 are
hereinafter collectively referred to as the "Guaranty Obligation."


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                                       5
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1.9            Notwithstanding the suspension, under the provisions of Section
6.3(a) of the COC, of the payment of any of the amounts included within the
Guaranty Obligation, it is agreed that the Guaranty Obligation covers all
payments which would have been due and payable during the Covered Fiscal Year
except for the fact that such payments were suspended pursuant to Section 6.3(a)
of the COC. Any such suspended payments shall be paid in the manner and within
the time provided in the COC, together with Late Payment Interest from the time
the suspended payments become due under the COC, and the Guarantors guarantee
the payment thereof, even after the expiration of the Covered Fiscal Year.

2.             Guarantors' Additional Agreements.

2.1            The Guarantors, in solido with each other and the Company, agree
to perform and comply with their Guaranty Obligation, whether or not the Company
is liable therefor individually or jointly or in solido with others, and whether
or not recovery against the Company is or may become barred by any statute of
limitations or prescriptive or preemptive period or is or may become
unenforceable or discharged, whether in whole or in part, for any reason other
than payment thereof in full. The Guarantors agree that this Guaranty is a
guaranty of payment and not of collection, and that their obligation under this
Guaranty shall be primary, absolute and unconditional,



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irrespective of, and unaffected by:

         (a) the absence of any action to enforce this Guaranty or any other
document or the waiver or consent by the LGCB with respect to any of the
provisions thereof;

         (b) any release or discharge of the other Guarantor, the Company or any
other party of the Guaranty Obligation; or

         (c) any other action or circumstances which might otherwise constitute
a legal or equitable discharge or defense of a surety or guarantor.

Each Guarantor shall be regarded, and shall be in the same position, as
principal debtor with respect to the Guaranty Obligation.

2.2            Each Guarantor expressly waives all rights it may have now or in
the future under any statute, or at common law, or at law or in equity, or
otherwise, to compel the LGCB to proceed in respect of the Guaranty Obligation
against the Company or any other party or against any security for the payment
of the Guaranty Obligation before proceeding against, or as a condition to
proceeding against, any Guarantor; and without limiting the above, each
Guarantor waives all pleas of division and discussion. Each Guarantor agrees
that any notice or directive given at any time to the LGCB which is inconsistent
with the



                                       7
<PAGE>

waiver in the immediately preceding sentence shall be null and void and may be
ignored by the LGCB, and in addition, may not be pleaded or introduced as
evidence in any litigation relating to this Guaranty for the reason that such
pleading or introduction would be at variance with the written terms of this
Guaranty, unless the LGCB has specifically agreed otherwise in writing.

2.3            Each Guarantor acknowledges that it has received a copy of and is
familiar with the COC, which to the extent of the Guaranty Obligation is
incorporated herein by reference.

2.4            Except as expressly provided for in this Guaranty, in no event
shall the Guarantors, as a result of this Guaranty, incur, directly or
indirectly, any obligation, contingent or otherwise, under the COC ("incur"
meaning to create, incur, assume, guaranty or otherwise become liable for).

3.             Alteration of the Guaranty Obligation.

3.1            No exercise or non-exercise of any right hereby given to the
LGCB, no dealing by the LGCB with the Guarantors or any other guarantor or any
other person, and no change, impairment or release of all or any portion of the
Company's COC obligations, or suspension of any right or remedy of the LGCB
against any person, including without limitation the Company or any other such
guarantor or other person, shall in any way affect any part of the Guaranty
Obligation or any security



                                       8
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furnished by the Guarantors or give the Guarantors any recourse against the
LGCB.

3.2            This Guaranty is provided on the express condition that, should
the LGCB and the Company amend or modify the COC so as to increase the Guaranty
Obligation or adversely affect the Guarantors without the prior written
agreement of the Guarantors, any such amendment or modification entered into
without the prior written agreement of the Guarantors shall not increase the
Guaranty Obligation or adversely affect the Guarantors.

4.             Waiver.

4.1            The Guarantors, in solido with each other, represent, warrant and
agree that, as of the date of this Guaranty, the Guaranty Obligation is not
subject to any recoupment, counterclaims, offsets or defenses against the LGCB
or the Company of any kind. The Guarantors further in solido with each other
agree that the Guaranty Obligation shall not be subject to any recoupment,
counterclaims, offsets or defenses against the LGCB or against the Company of
any kind which may arise in the future. Each Guarantor hereby expressly waives
and relinquishes all rights, defenses and remedies accorded by applicable law to
sureties or guarantors and agrees not to assert or take advantage of any such
rights, defenses or remedies, including without limitation:



                                       9
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         (a) any right to require the LGCB to proceed against the Company or any
other person or to proceed against or exhaust any security held by the LGCB at
any time or to pursue any other remedy in the power of the LGCB before
proceeding against either or both of the Guarantors, including but not limited
to any defense of failure to join or non-joinder of the Company or any other
person whatsoever in any litigation instituted by the LGCB against either or
both of the Guarantors;

         (b) the defense of any statute of limitation, prescription and
preemption in any action hereunder or in any action for the collection of any of
the Guaranty Obligation;

         (c) any defense that may arise by reason of the discharge in
bankruptcy, incapacity, lack of authority, death or disability of any other
person (including the Company) or the failure of the LGCB to file or enforce a
claim against the estate (in administration, bankruptcy or any other proceeding)
of any other person (including the Company);

         (d) diligence, demand, presentment, protest and notice of any kind
other than notices expressly required in this Guaranty (whether for nonpayment
or protest or of acceptance, maturity, extension of time, change in nature or
form of the Company's obligations under the COC, acceptance of further security,
release of further security, composition or agreement arrived at



                                       10
<PAGE>

as to the amount of, or the terms of, the Company's obligations under the COC,
notice of adverse change in the Company's financial condition or any other fact
which might materially increase the risk to the Guarantors), including without
limitation notice of the existence, creation or incurring of any new or
additional indebtedness or obligation or of any action or non-action on the part
of the Company, the LGCB, any endorser or creditor of the Company or either
Guarantor or on the part of any other person under this or any other instrument
in connection with any obligation or evidence of indebtedness held by the LGCB
in connection with any of the obligations of the Company under the COC;

         (e) any defense based upon an election of remedies by the LGCB which
destroys or otherwise impairs the subrogation rights of the Guarantors, the
right of the Guarantors to proceed against the Company for reimbursement, or
both, or any defense that the LGCB's claims against the Guarantors are barred or
diminished or premature to the extent that the LGCB has or may have remedies
available against the Company;

         (f) any defense based upon any statute or rule of law which provides
that the obligation of a surety must be neither larger in amount nor in other
respects more burdensome than that of the principal;


                                       11
<PAGE>

         (g) any duty on the part of the LGCB to disclose to the Guarantors any
facts the LGCB may now or hereafter know about the Company, regardless of
whether the LGCB has reason to believe that any such facts materially increase
the risk beyond that which the Guarantors intend to assume, or has reason to
believe that such facts are unknown to either Guarantor, or has a reasonable
opportunity to communicate such facts to either Guarantor, since each Guarantor
acknowledges that it is fully responsible for being and keeping informed of the
financial condition of the Company and of all circumstances bearing on the risk
of nonpayment of any of the obligations of the Company under the COC;

         (h) waiver or estoppel or any alleged lack of reasonable or justifiable
reliance on the part of the LGCB as to the Guarantors' representations;

         (i) lack, failure or insufficiency of consideration;

         (j) subject to the notice requirements of Sections 1.4 and 1.5 hereof,
any alleged failure of the LGCB to mitigate injuries, losses or damages or any
plea that the LGCB has any duty to mitigate injuries, losses, or damages prior
to seeking recovery under this Guaranty; and

         (k) any defense that the LGCB's claims hereunder are or may be barred
because any adequate remedy at law exists.



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<PAGE>

4.2            Following any default by either Guarantor under this Guaranty,
each Guarantor agrees to forbear from exercise of any rights of subrogation,
indemnity, or contribution against each other, the Company or any other person
who may be liable for satisfaction of the Guaranty Obligation until the Guaranty
Obligation has been fully satisfied as to the LGCB.

5.             Bankruptcy.

5.1            In the event of the commencement of a bankruptcy case by or
against any Guarantor, each Guarantor agrees to waive the automatic stay under
the Bankruptcy Code and further agrees to the entry of an immediate order from
the Bankruptcy Court, on the LGCB's ex parte motion granting to the LGCB a
modification of the automatic stay (and/or recognition that the automatic stay
is not applicable) allowing it to fully enforce the provisions of this Guaranty,
the Guarantors hereby agreeing that in such case, "cause," as defined by the
Bankruptcy Code, would exist for the immediate entry by the Bankruptcy Court of
such an order modifying the automatic stay.

5.2            The Guaranty Obligation shall not be altered, limited or affected
by any proceeding, voluntary or involuntary, involving the bankruptcy,
reorganization, insolvency, receivership, liquidation or arrangement of the
Company, or by any defense which the Company may have by reason of any order,


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decree or decision of any court or administrative body resulting from any such
proceeding.

5.3            This Guaranty shall remain in full force and effect and continue
to be effective should any petition be filed by or against the Company or any
Guarantor for liquidation or reorganization, should the Company or any Guarantor
become insolvent or make an assignment for the benefit of creditors or should a
receiver or trustee be appointed for all or any significant part of the
Company's or any Guarantor's assets, and shall continue to be effective or be
reinstated, as the case may be, if at any time payment of the Guaranty
Obligation, or any part thereof, is, pursuant to applicable law, rescinded or
reduced in amount or must otherwise be restored or returned by the LGCB, whether
as a "voidable preference," "fraudulent conveyance," or otherwise, all as though
such payment had not been made. In the event that any payment, or any part
thereof, is rescinded, reduced, restored or returned, the Guaranty Obligation
shall be reinstated and deemed reduced only by such amount paid and not so
rescinded, reduced, restored or returned.

6.             Interest, Costs and Attorneys' Fees.

6.1            If the Guarantors fail to timely pay all or any portion of the
Guaranty Obligation in accordance with the provisions of Section 1 of this
Guaranty, such amount shall bear interest as provided in Section 1.2 of this
Guaranty.



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6.2            If the LGCB refers this Guaranty to an attorney to enforce,
construe, or defend any provision hereof, or as a consequence of any default
hereunder by the Guarantors in connection with:

         (a) any litigation, contest, dispute, suit, proceeding or action
(whether instituted by the LGCB, the Company, the Guarantors or any other
person) in any way relating to the enforcement of rights or remedies under this
Guaranty;

         (b) any attempt to enforce any rights of the LGCB hereunder against the
Guarantors or any other person; or

         (c) any attempt to defend any provision hereof;

then, and in any such event, the attorneys' fees arising from such services,
including those of any appellate proceedings, and all expenses, costs, charges
and other fees incurred by such counsel and others in any way or respect arising
in connection with or relating to any of the events or actions described herein
shall be payable, on demand, by the Guarantors to the LGCB or the Guarantors
shall cause the Company to make such payment, and if not so paid, shall be a
part of the Guaranty Obligation. The reference to "attorneys' fees" in this
Section 6.2 and in all other places in this Guaranty shall also include, without
limitation, such reasonable amounts as may then be



                                       15
<PAGE>

charged for legal services furnished by attorneys retained or employed by the
State or the LGCB. Such attorneys' fees, costs and expenses shall include,
without limitation, those incurred in connection with any bankruptcy,
reorganization, insolvency, receivership, liquidation, arrangement, lawsuits in
state or federal court, or other similar proceedings involving either Guarantor
which in any way affect the exercise by the LGCB of its rights and remedies
hereunder.

7.             Cumulative Rights.

               All rights, powers and remedies of the LGCB hereunder and under
any other written agreement now or at any time hereafter in force between the
LGCB and the Guarantors, including without limitation any other guaranty
executed by either Guarantor relating to any indebtedness of the Company, shall
be cumulative and not alternative, and such rights, powers and remedies shall be
in addition to all rights, powers and remedies given to the LGCB by law and
shall not be deemed in any way to extinguish or diminish the LGCB's rights and
remedies. This Guaranty is in addition to and independent of the guaranty of any
guarantor of any other obligations of the Company under the COC or other
indebtedness of the Company.


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<PAGE>

8.             Application of Payments and Recoveries.

               After a Minimum Payment Default has occurred, as to any payments
received directly from a Guarantor, the LGCB shall apply such payments to
amounts due under the Guaranty Obligation. Any other payments or recoveries
received by the LGCB after a Minimum Payment Default shall be applied, as
directed by the LGCB at its sole option, (a) first, to amounts due for any
Additional Charges, and (b) second, to any Daily Payments, Required Payments, or
Minimum Payment due for any Fiscal Year other than the Fiscal Year in which the
Minimum Payment Default has occurred (collectively, the "Other Fiscal Year
Payments"). Only when such Additional Charges and all Other Fiscal Year Payments
are paid current will any payments or recoveries be applied to the Guaranty
Obligation under this Guaranty Agreement; provided, however, Daily Payments,
Required Payments or Minimum Payments paid by the Company during a Covered
Fiscal Year shall be applied to the Minimum Payment for that Covered Fiscal
Year.

9.             Independent Obligations.

               The Guaranty obligation is independent of the obligations of the
Company under the COC, and, in the event of any default hereunder, a separate
action or actions may be brought and prosecuted against either Guarantor,
whether or not the Company is joined therein or a separate action or actions are
brought



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against the Company. The LGCB's rights hereunder shall not be exhausted by its
exercise of any of its rights or remedies or by any such action or by any number
of successive actions unless and until all Guaranty Obligations have been
satisfied and fully performed.

10.            Financial Statements.

               The Guarantors hereby represent and warranty that the information
pertaining to the Guarantors set forth in their most recent filings with the
Securities and Exchange Commission is true and correct in all material respects,
and fairly presents the financial condition of the Guarantors as of the
respective dates indicated therein and for the periods covered thereby, and that
no material adverse change has occurred in the financial condition or prospects
of the Guarantors since the date of the latest information provided therein.

11.            Notices.

               Whenever the Guarantors or the LGCB shall desire to give or
serve any notice, demand, request or other communication with respect to this
Guaranty, each such notice shall be in writing and shall be effective only if
the same is delivered by personal service, overnight courier service, or mailed
by certified mail, postage prepaid, return receipt requested, addressed as
follows:



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<PAGE>

         (a)       if to either Guarantor
                   (or both Guarantors):

                   HET and Harrah's Operating
                   c/o Harrah's Entertainment, Inc.
                   5100 West Sahara Ave.
                   Las Vegas, Nevada 89146
                   Attention:  General Counsel

         (b)       if to the LGCB, as provided in the COC;

or at such other address as shall have been furnished in writing by any person
described above to the party required to give notice hereunder. Any such notice
shall be deemed to have been received upon delivery. Any of the Guarantors or
the LGCB may change its address by giving the others written notice of the new
address as herein provided.

12.            Successors and Assigns.

               This Guaranty shall inure to the benefit of the LGCB, its
successors and assigns, and shall bind the successors and assigns of each
Guarantor. Neither Guarantor may assign or transfer any of its rights,
obligations or interest hereunder without the prior written consent of the LGCB.


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13.            Miscellaneous Provisions.

13.1           This Guaranty shall be governed, interpreted and enforced in
accordance with Louisiana law.

         Each Guarantor hereby submits to the jurisdiction of the State and the
courts thereof and to the jurisdiction of the Nineteenth Judicial District Court
in and for East Baton Rouge Parish ("19th JDC") for purposes of any suit, action
or other proceeding arising out of or relating to this Guaranty and agrees not
to assert by way of motion as a defense or otherwise that such suit, action or
other proceeding is brought in an inconvenient forum or that the venue of such
suit, action or other proceeding is improper or that the subject matter thereof
may not be enforced in or by such court or assert that any suit or action filed
in the 19th JDC may be removed to the Federal Court, and each Guarantor agrees
that the 19th JDC shall have the exclusive jurisdiction for purposes of any
suit, action or other proceeding brought by either of them relating to or
arising out of this Guaranty.

         If at any time during the Term, either Guarantor is not a resident of
the State and has not formally designated or does not continuously maintain an
agent for service of process in Louisiana or has not notified LGCB of the full
name and current street address in Louisiana of such agent for service of
process, such Guarantor hereby designates the Secretary of State



                                       20
<PAGE>

of Louisiana as its agent for service of process in any suit, action or
proceeding involving the LGCB or the State or arising out of or relating to this
Guaranty, and such service shall be made as provided by Louisiana law for
service on an insurance company through the Secretary of State.

13.2           This Guaranty shall constitute the entire agreement of the
Guarantors with the LGCB with respect to the subject matter hereof, and no
representation, understanding, promise or condition concerning the subject
matter hereof shall be binding upon the LGCB or the Guarantors unless expressed
herein.

13.3           Should any term, covenant, condition or provision of this
Guaranty be determined to be illegal or unenforceable, it is the intent of the
parties that all other terms, covenants, conditions and provisions hereof shall
nevertheless remain in full force and effect.

13.4           Time is of the essence to this Guaranty and each of its
provisions.

13.5           When the context and construction so require, all words used in
the singular herein shall be deemed to include the plural, the masculine shall
include the feminine and neuter, and vice versa.



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<PAGE>

13.6           The word "person" as used herein shall include any individual,
company, firm, association, partnership, limited liability company, joint
venture, corporation, trust or other legal entity of any kind whatsoever.

13.7           No provision of this Guaranty or right granted to the LGCB
hereunder can be waived in whole or in part, nor can either Guarantor be
released from the Guaranty Obligation, except by an express and specific writing
to that effect duly executed by an authorized officer of the LGCB. No provision
of this Guaranty may be amended without the prior written consent of the
Guarantors and the LGCB and the consent of any additional beneficiaries hereof,
if any, shall not be required.

13.8           The LGCB need not inquire into the power of the Guarantors or the
authority of their officers, shareholders or agents acting or purporting to act
on their behalf.

13.9           The headings of this Guaranty are inserted for convenience only
and shall have no effect upon the construction or interpretation thereof.

13.10          All of the representations, warranties, agreements, obligations
and covenants of each Guarantor are in solido with the other Guarantor. This
Guaranty shall be for the sole benefit of the State of Louisiana acting by and
through the LGCB, its successors and assigns. The provisions of this



                                       22
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Guaranty shall not inure to the benefit of any other person, including, without
limitation, the Company.

13.11          This Guaranty shall be effective upon execution.


         IN WITNESS HEREOF, the undersigned have executed this Guaranty as of
the 28th day of March, 2000.


                                            GUARANTORS:

                                            HARRAH'S ENTERTAINMENT, INC.


                                            By:  /s/ Stephen Brammell
                                                 ---------------------------
                                                 Duly Authorized Officer


                                            HARRAH'S OPERATING COMPANY, INC.


                                            By:  /s/ Stephen Brammell
                                                 ----------------------------
                                                 Duly Authorized Officer



                                       23
<PAGE>

Approved and consented to:


JAZZ CASINO COMPANY, L.L.C.


By: /s/ Frederick W. Burford
    ------------------------------
    Duly Authorized Officer


Accepted and agreed to:


LOUISIANA GAMING CONTROL BOARD


By:  /s/ Hillary J. Crain
     -----------------------------
     Name:    Hillary J. Crain
     Title:   Chairman



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