Kriegspiel

Kriegspiel is a German word for wargame. In particular, Kriegspiel is a historical term used to discuss wargames conducted by the Prussian and German military. See also: Wargaming.

Kriegspiel is also the name of a chess variant, in which each player can see their own pieces, but not those of their opponent. For this reason, it is necessary to have a third person act as a referee.