Crazyhouse is a chess variant that follows most of the normal rules of chess, except that captured pieces can be reintroduced to the board on your side. It was derived as a two-player, single-board variant of bughouse chess. The game is often compared to shogi, but there is no known evidence suggesting that shogi provided direct inspiration for the gameplay of bughouse or crazyhouse.
The rules of chess apply except for the addition of drops, as explained below:
- A captured piece can be reintroduced to the board on your side as one of your own pieces.
- Pawns and knights increase in relative importance in Crazyhouse, while rooks, queens, and bishops decrease in relative importance.
- If a king is put in check by a rook, queen, or bishop from two or more squares away, dropping a pawn next to the king becomes defensively useful. A knight, on the other hand, cannot be blocked by anything and its offensive value is more manifest.
- All the normal chess themes are heightened by magnitudes in Crazyhouse. An extra tempo or two can lead to a crushing attack, and even small weaknesses, when exploited correctly, can become glaring. Precision is almost always required, especially when defending, as every position is a sharp one.
Crazyhouse has several related variants, including Loop Chess and Chessgi. It became prominent in the era of 1990s online chess servers. Crazyhouse is a popular game that can stand on its own merits, and becoming proficient in Crazyhouse can help improve chess vision.
