
thumb|upright=1.45|1.N@e7+ Kh8 2.Bxg7# (#Notation|@ notation) Crazyhouse is a chess variant in which captured enemy pieces can be reintroduced, or dropped, into the game as one's own, similarly to shogi. It was derived as a two-player, single-board variant of bughouse chess.
thumb|upright=1.45|1.N@e7+ Kh8 2.Bxg7# (#Notation|@ notation) Crazyhouse is a chess variant in which captured enemy pieces can be reintroduced, or dropped, into the game as one's own, similarly to shogi. It was derived as a two-player, single-board variant of bughouse chess.
== History == Though the four-player "bughouse" chess became prominent in western chess circles in the 1960s, the crazyhouse variant did not rise to prominence until the era of 1990s online chess servers, though it may be traced back further to the "Mad Mate" variant made in 1972 by Alex Randolph, a Bohemian-American game designer who moved to Japan and became an amateur dan-level Shogi player.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).