Kriegspiel (chess) follows. The game is played with three boards, one for each player; the third is for the umpire (and spectators). Each opponent knows the exact position of just their pieces, and does not know where the opponent's pieces are (but can keep track of how many there are). Only the umpire knows the position of the game. The game proceeds in the following way: The umpire announces: Pawn promotions are not announced. Kriegspiel is sometimes used in chess problems. In these, usual variations introduced by different black moves are replaced by variations introduced by different announcements. An example of a
Kung-Fu Chess Chess contained six different game types: in addition to the four existed in Shizmoo's Kung-Fu Chess, also included Fast Standard, and Four-Way Crazyhouse. On May 27, 2014 Tempest was discontinued by its owner. In 2010 a game similar to Kung Fu Chess dubbed "Ninja Chess" has been developed for iPhone and iPad. It is published on the App Store by Nordlysa Entertainment, but has been abandoned by the creator and is currently unavailable from the Store. This project brings the concept of Real-Time Chess to touch interfaces and includes the ability to play Head-to-Head (each player facing his own board).