According to the Terminology of the Imperium appendix of Dune, Cheops is a nine-level pyramid chess game with the double object of putting the queen piece at the apex and the opponent's king in check. [For actual game details (including rules and setup), check out the Cheops home page.] It had been once played on Arrakis by Crown Prince Leto Atreides II and his younger twin-sister, Crown Princess Ghanima Atreides I. [For more (fictional) game history, check out the Cheops entry in the Dune Encyclopedia.]