EXHIBIT 99.1
SUPPLEMENTAL AGREEMENT OF AMERISTAR CASINOS, INC.
Ameristar Casinos, Inc. ("ACI") hereby agrees to furnish
supplementally to the Securities and Exchange Commission a copy
of any of the following instruments defining the rights of
holders of long-term debt issued by ACI or its subsidiaries:
1. Purchase Money Deed of Trust Note executed by Ameristar
Casino Vicksburg, Inc., a Mississippi corporation ("ACVI"), in
favor of Magnolia Hotel Company, a Mississippi corporation
("Magnolia"), in the principal amount of $250,000.
2. Purchase Money Deed of Trust Note executed by ACVI in favor
of Magnolia in the principal amount of $4,329,725.85.
In addition, ACI hereby agrees to furnish supplementally to the
Securities and Exchange Commission a copy of all omitted exhibits
and schedules to the Asset Purchase and Sale Agreement filed as
Exhibit 10.12 to this Annual Report.