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                                                                     EXHIBIT 4.6


                                FOURTH AMENDMENT

               FOURTH AMENDMENT (this "Amendment"), dated as of December 16th,
1999, among ALLIANCE GAMING CORPORATION, a Nevada corporation (the "U.S.
Borrower"), BALLY WULFF VERTRIEBS GMBH, a company with limited liability
organized under the laws of the Federal Republic of Germany ("Bally Wulff
Vertriebs"), BALLY WULFF AUTOMATEN GMBH, a company with limited liability
organized under the laws of the Federal Republic of Germany ("Bally Wulff
Automaten" and, together with Bally Wulff Vertriebs, the "German Borrowers," and
each a "German Borrower", and the German Borrowers, together with the U.S.
Borrower, the "Borrowers," and each a "Borrower"), the financial institutions
party to the Credit Agreement referred to below (the "Lenders") and CREDIT
SUISSE FIRST BOSTON, as Administrative Agent. Unless otherwise defined herein,
all capitalized terms used herein and defined in the Credit Agreement referred
to below are used herein as so defined.

                                  WITNESSETH:

               WHEREAS, the Borrowers, the Lenders and the Administrative Agent
are parties to a Credit Agreement, dated as of August 8, 1997 (as amended,
modified or supplemented through, but not including, the date hereof, the
"Credit Agreement");

               WHEREAS, the parties hereto wish to further amend the Credit
Agreement as herein provided;

               NOW, THEREFORE, it is agreed:

               1. The definition of "Consolidated EBITDA" appearing in Section
11 of the Credit Agreement is hereby amended by deleting the last sentence of
said definition and inserting the following sentence in lieu thereof:

               "For the purposes of calculating Consolidated EBITDA for (A) any
period ending on or prior to December 31, 2000, any determination of
Consolidated Net Income shall be adjusted by adding thereto (A) the amount of
any restructuring charges taken during such period at Bally Gaming, Inc., (B)
the amount of any restructuring charges taken during such period in connection
with the RCVP Sale, the Nevada Route Operations Sale, the Rail City Sale, the
Louisiana Route Operations Sale or any of the transactions contemplated in
Section 1 of Article I of the Third Amendment and (C) any ancillary transaction
costs incurred in connection with the RCVP Sale, the Nevada Route Operations
Sale, the Rail City Sale or the Louisiana Route Operations Sale, provided that
(x) the sum of the charges described in clause (A) shall not exceed $1,500,000,
and (y) the sum of the charges described in clauses (A) and (B) taken together
shall not exceed $7,000,000."

               2. This Amendment shall become effective on the date (the "Fourth
Amendment Effective Date") when each Borrower, each other Credit Party and the
Required Lenders have signed a counterpart hereof (whether the same or different
counterparts) and shall have delivered (including by way of facsimile
transmission) the same to the Administrative Agent at the Notice Office.
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               3. In order to induce the Lenders to enter into this Amendment,
each Borrower hereby represents and warrants that (i) the representations and
warranties contained in Section 7 of the Credit Agreement are true and correct
in all material respects on and as of the Fourth Amendment Effective Date both
before and after giving effect to this Amendment (it being understood and agreed
that, as to any representation or warranty which by its terms is made as of a
specified date, each Borrower represents and warrants that such representation
and warranty is true and correct in all material respects only as of such
specified date) and (ii) there exists no Default or Event of Default on the
Fourth Amendment Effective Date both before and after giving effect to this
Amendment.

               4. This Amendment is limited as specified and shall not
constitute a modification, acceptance or waiver of any other provision of the
Credit Agreement or any other Credit Document.

               5. This Amendment may be executed in any number of counterparts
and by the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the U.S. Borrower and the Administrative
Agent.

               6. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

               7. From and after the Fourth Amendment Effective Date, all
references in the Credit Agreement and in the other Credit Documents to the
Credit Agreement shall be deemed to be references to the Credit Agreement as
amended hereby.

                                     * * *

               IN WITNESS WHEREOF, the parties hereto have caused their duly
authorized officers to execute and deliver this Amendment as of the date first
above written.

                                         ALLIANCE GAMING CORPORATION

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       2
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                                         BALLY WULFF VERTRIEBS GMBH

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         BALLY WULFF AUTOMATEN GMBH

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         CREDIT SUISSE FIRST BOSTON,
                                           Individually and as Administrative
                                           Agent

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         THE BANK OF NOVA SCOTIA

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       3
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                                         KZH ING-1 LLC

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         SUMITOMO BANK OF CALIFORNIA

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         THE MITSUBISHI TRUST AND BANKING CORP.

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         SOUTHERN PACIFIC BANK

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       4
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                                         CRESCENT/MACH I PARTNERS

                                         By:  TCW Asset Management Company, Its
                                              Investment Advisor

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         MERRILL LYNCH SENIOR FLOATING RATE
                                           FUND, INC.

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         TCW LEVERAGED INCOME TRUST, L.P.

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         VAN KAMPEN PRIME RATE INCOME TRUST

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       5
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                                         VAN KAMPEN CLO I, LIMITED

                                         By:  VAN KAMPEN MANAGEMENT INC., as
                                              Collateral Manager

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         INDOSUEZ CAPITAL FUNDING III, LIMITED

                                         By:  Indosuez Capital, as Portfolio
                                              Advisor

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         DEEPROCK & COMPANY

                                         By:  Eaton Vance Management As
                                              Investment Advisor

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         ML CLO XII PILGRIM AMERICA
                                         (Cayman) LTD.

                                         By:  Pilgrim Investments, Inc. as its
                                              Investment  Manager

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       6
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                                      MORGAN STANLEY DEAN WITTER PRIME INCOME
                                        TRUST

                                      By /s/
                                         ------------------------------------
                                         Name:
                                         Title:

                                      DELANO COMPANY

                                      By:  Pacific Investment Management
                                             Company, as its Investment Advisor


                                      By /s/
                                         ------------------------------------
                                         Name:
                                         Title:


                                      SENIOR DEBT PORTFOLIO

                                      By:  Boston Management and Research as
                                           Investment Advisor

                                      By /s/
                                         ------------------------------------
                                         Name:
                                         Title:


                                      KZH-CRESCENT CORP.

                                      By /s/
                                         ------------------------------------
                                         Name:
                                         Title:


                                       7
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                                         PAMCO CAYMAN LTD.

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         CYPRESSTREE INVESTMENT PARTNERS I,
                                           LTD.,

                                         By:  Cypresstree Investment Management
                                              Company, Inc., as Portfolio
                                              Manager

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         TEXAS COMMERCE BANK


                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         ARCHIMEDES FUNDING, L.L.C.

                                         By:  ING Capital Advisors, Inc., as
                                              Collateral Manager

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                       8
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                                         GENERAL ELECTRIC CAPITAL CORPORATION

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         MASSMUTUAL HIGH YIELD
                                              PARTNERS I, LLC

                                         By:  HYP Management, Inc., as Managing
                                              Member

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


                                         Its:
                                              ----------------------------------

                                         CALIFORNIA BANK & TRUST

                                         By /s/
                                            ------------------------------------
                                            Name:
                                            Title:


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