AMENDMENT NUMBER 4 TO LOAN AND SECURITY AGREEMENT

Exhibit 10.31

AMENDMENT NUMBER 4 TO LOAN AND SECURITY AGREEMENT

THIS AMENDMENT NUMBER 4 TO LOAN AND SECURITY AGREEMENT (this “Amendment”), is entered into as of March 22, 2004, by and among, on the one hand WELLS FARGO FOOTHILL, INC., a California corporation, formerly known as Foothill Capital Corporation (“Lender”) and, on the other hand MIKOHN GAMING CORPORATION, a Nevada corporation (“Borrower”), and the other Obligors identified on the signature pages hereof.

W I T N E S S E T H

WHEREAS, Borrower, the other Obligors and Lender are parties to that certain Loan and Security Agreement, dated as of February 14, 2002 (as amended, restated, supplemented, or modified from time to time, the “Loan Agreement”);

WHEREAS, that certain Amendment Number 3 to Loan and Security Agreement (the “Third Amendment”), dated as of January 21, 2004, by and among the parties to the Loan Agreement, provides, among other things, for an amended definition of “Consolidated EBITDA” to allow up to $6,300,000 in cash and non-cash restructuring charges for Borrower’s fiscal quarter ending December 31, 2003;

WHEREAS, following the execution of the Third Amendment, Borrower has learned and advised Lender that Borrower’s restructuring charges for its fiscal quarter ending December 31, 2003 will be $15,300,000.

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties agree to amend the Loan Agreement as follows:

1. DEFINITIONS. Capitalized terms used herein and not otherwise defined herein shall have the meanings ascribed to them in the Loan Agreement, as amended hereby.

2. AMENDMENTS TO LOAN AGREEMENT.

(a) Section 1.1 of the Loan Agreement is hereby amended by amending and restating the following definition in its entirety:

“Consolidated EBITDA” means, with respect to any Person, for any period, the Consolidated Net Income of such Person for such period adjusted to add thereto (to the extent deducted from net revenues in determining Consolidated Net Income), without duplication, the sum of

(1) Consolidated income tax expense;

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(2) Consolidated depreciation and amortization expense;

(3) Consolidated Interest Expense;

(4) All other non-cash charges attributable to the grant, exercise or repurchase of options for or shares of Qualified Capital Stock to or from employees of such Person and its Consolidated Subsidiaries; and

(5) With respect to Borrower, one-time charges aggregating no more than $15,300,000 related to bond redemption expenses, write-offs of fixed assets, office closure expenses and severance expenses; each such charge as demonstrated to Lender’s satisfaction and taken during the fiscal quarter of Borrower ending December 31, 2003.”

3. REAFFIRMATION AND CONSENT. Each Guarantor hereby (a) represents and warrants to Lender that the execution, delivery, and performance of this Amendment are within its powers, have been duly authorized by all necessary action, and are not in contravention of any law, rule, or regulation, or any order, judgment, decree, writ, injunction, or award of any arbitrator, court, or governmental authority, or of the terms of its charter or bylaws, or of any contract or undertaking to which it is a party or by which any of its properties may be bound or affected; (b) consents to the transactions contemplated by this Amendment; (c) acknowledges and reaffirms its obligations owing to Lender under any Loan Documents to which it is a party; and (d) agrees that each of the Loan Documents to which it is a party is and shall remain in full force and effect. Although each Guarantor has been informed of the matters set forth herein and has acknowledged and agreed to same, it understands that Lender has no obligations to inform it of such matters in the future or to seek its acknowledgement or agreement to future amendments, and nothing herein shall create such a duty.

4. CONDITIONS PRECEDENT TO THIS AMENDMENT. The satisfaction of each of the following shall constitute conditions precedent to the effectiveness of this Amendment and each and every provision hereof:

(a) The representations and warranties in the Loan Agreement and the other Loan Documents shall be true and correct in all respects on and as of the date hereof, as though made on such date (except to the extent that such representations and warranties relate solely to an earlier date);

(b) No Default or Event of Default shall have occurred and be continuing on the date hereof or as of the date of the effectiveness of this Amendment; and

(c) No injunction, writ, restraining order, or other order of any nature prohibiting, directly or indirectly, the consummation of the transactions contemplated herein shall have been issued and remain in force by any Governmental Authority against any Obligor or Lender.

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5. CONSTRUCTION. THIS AMENDMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEVADA APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED IN THE STATE OF NEVADA.

6. ENTIRE AMENDMENT; EFFECT OF AMENDMENT. This Amendment constitutes the entire agreement among the parties pertaining to the subject matter hereof and supersedes any and all prior or contemporaneous amendments relating to the subject matter hereof. Except for the amendments to the Loan Agreement expressly set forth in Section 2 hereof, the Loan Agreement and other Loan Documents shall remain unchanged and in full force and effect. To the extent any terms or provisions of this Amendment conflict with those of the Loan Agreement or other Loan Documents, the terms and provisions of this Amendment shall control. This Amendment is a Loan Document.

7. COUNTERPARTS; TELEFACSIMILE EXECUTION. This Amendment may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument and any of the parties hereto may execute this Amendment by signing any such counterpart. Delivery of an executed counterpart of this Amendment by telefacsimile shall be equally as effective as delivery of an original executed counterpart of this Amendment. Any party delivering an executed counterpart of this Amendment by telefacsimile also shall deliver an original executed counterpart of this Amendment, but the failure to deliver an original executed counterpart shall not affect the validity, enforceability, and binding effect of this Amendment.

8. MISCELLANEOUS.

(a) Upon the effectiveness of this Amendment, each reference in the Loan Agreement to “this Agreement,” “hereunder,” “herein,” “hereof” or words of like import referring to the Loan Agreement shall mean and refer to the Loan Agreement as amended by this Amendment.

(b) Upon the effectiveness of this Amendment, each reference in the Loan Documents to the “Loan Agreement,” “thereunder,” “therein,” “thereof” or words of like import referring to the Loan Agreement shall mean and refer to the Loan Agreement as amended by this Amendment.

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IN WITNESS WHEREOF, the parties have caused this Amendment to be executed and delivered as of the date first written above.

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