Chess Variants/Extinction Chess

Introduction
Extinction Chess is a variant which give every piece the same role as the king - lose them, and you lose the game.

History
Extinction chess was created by R. Wayne Schmittberger, the editor of Games magazine, in 1985.

Rules
Extinction chess is played exactly like the standard game, with one key difference - checkmate is no longer the objective. Instead, the objective is to eliminate all of a particular type of the opponent's pieces. So, there are six ways to achieve victory:


 * Capture the opponent's king
 * Capture the opponent's queen
 * Capture both of the opponent's bishops
 * Capture both of the opponent's knights
 * Capture both of the opponent's rooks
 * Capture all eight of the opponent's pawns

The king in extinction chess does not have royal power. Ergo, it may capture and be captured just like any other piece, there is no check or checkmate, and a pawn may promote to a king if it wishes.

A promoted pawn is no longer considered a pawn, but rather the type of piece it promotes to. So if a pawn promotes to a queen, both queens must be captured to achieve victory, and if a player promotes their last pawn, they automatically lose the game.

There can be situations where pawn promotion brings about extinction for both sides. For example, say White has their last pawn on b7 and Black their last bishop on c8. If white plays bxc8=(any), then both the white pawns and black bishops will be extinct. In this case White is ruled to have won, since it was a White move that brought this situation around, and also because this move is thought of as having two parts (the bishop is removed from the board before the pawn is promoted).

Sub-variants
This chess variant does not not have any notable sub-variants.