The Pinnacle Entertainment, Inc. logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=13121About Ameristar Casinos Ameristar Casinos is an innovative casino gaming company featuring the newest and most popular slot machines. Ameristar has 7,200 dedicated team members who pride themselves on delivering consistently friendly and appreciative service to their guests. Ameristar continuously strives to increase the loyalty of its guests through the quality of its slot machines, table games, hotel, dining and other leisure offerings. Ameristar's eight casino hotel properties primarily serve guests from Colorado, Idaho, Illinois, Indiana, Iowa, Kansas, Louisiana, Mississippi, Missouri, Nebraska and Nevada. Ameristar has been a public company since 1993, and its stock is traded on the Nasdaq Global Select Market. Ameristar generates more than $1.1 billion in net revenues annually. The Ameristar Casinos, Inc. Logo is available a http://www.globenewswire.com/newsroom/prs/?pkgid=16403 Additional Information and Where to Find It In connection with the proposed merger, Ameristar plans to file a proxy statement with the SEC and mail the proxy statement to its stockholders. INVESTORS AND STOCKHOLDERS ARE URGED TO READ THE PROXY STATEMENT AND OTHER PROXY MATERIALS WHEN THEY BECOME AVAILABLE AS THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT PINNACLE, AMERISTAR, THE PROPOSED MERGER AND RELATED MATTERS. The proxy statement, as well as other filings containing information about Pinnacle and Ameristar will be available, free of charge, from the SEC's web site ( www.sec.gov). Pinnacle's SEC filings in connection with the transaction also may be obtained, free of charge, from Pinnacle's web site ( www.pnkinc.com) under the tab "Investor Relations" and then under the heading "SEC Filings," or by directing a request to Pinnacle, 8918 Spanish Ridge Ave., Las Vegas, Nevada, 89148, Attention: Investor Relations or (702) 541-7777. Ameristar's SEC filings in connection with the transaction also may be obtained, free of charge, from Ameristar's web site ( www.ameristar.com ) under the tab "About Us," "Investor Relations" and then under the heading "Ameristar SEC Reports & Filings," or by directing a request to Ameristar, 3773 Howard Hughes Parkway, Suite 490 South, Las Vegas, Nevada, 89169, Attention: Investor Relations or (702) 567-7000. Participants in the Merger Solicitation Pinnacle and Ameristar and their respective directors and executive officers and other persons may be deemed to be participants in the solicitation of proxies in connection with the proposed merger. Information about Pinnacle's directors and executive officers is included in Pinnacle's Annual Report on Form 10-K/A for the year ended December 31, 2011, filed with the SEC on May 16, 2012 and the proxy statement for Pinnacle's 2012 Annual Meeting of Stockholders, filed with the SEC on April 9, 2012. Information about Ameristar's directors and executive officers is included in Ameristar's Annual Report on Form 10-K for the year ended December 31, 2011, filed with the SEC on February 28, 2012 and the proxy statement for Ameristar's 2012 Annual Meeting of Stockholders, filed with the SEC on April 30, 2012. Additional information regarding these persons and their interests in the merger will be included in the proxy statement relating to the merger when it is filed with the SEC. These documents can be obtained free of charge from the sources indicated above.