The most immediate ancestor of chess is, which became popular in the seventh century in Persia. This game, available on some online chess servers, was very similar to modern chess, with a few major changes. The kings, rooks, and knights are identical to those we use today. Pawns can only move one square, the queen (known as a fers or counsellor) could only move one square in any diagonal direction, and the bishop (or elephant) jumped like a knight—but only two squares diagonally. Crazyhouse is bughouse for just two players. It is played like normal chess, except that capturing a piece allows a player to place the same piece of his color on the board later, as in bughouse. The difference is how the starting position is determined. The pawns are placed along the second rank, as in a normal game. However, the arrangement of the other pieces is randomized, with just a few rules governing how the pieces are arrayed. The black position always mirrors the white position, each side must have one bishop of each color, and the kings are always placed between the rooks. Within those rules, there are 960 possible starting positions, which can be determined by dice or other methods before the game begins. The chancellor can move like a knight or a rook. The archbishop can move like a knight or a bishop. Both pieces are quite powerful; the chancellor is nearly as strong as a queen, while the archbishop is the only piece that can checkmate without any help from friendly or enemy pieces. Other than these new pieces, these games are played with the same rules as standard chess. These games often have varying rules but are generally played with just a few rule changes from standard chess. Captures are mandatory—if a player has a choice of captures, he can make whichever one he likes, but cannot choose to refrain from taking a piece. Kings are treated like normal pieces and can be captured at any time. The winner is the first player to lose all of their pieces, or, in some variants, to be unable to make a legal move. Given the logistical difficulty of Kriegspiel, it can only be played with the help of an arbiter—either a human or a chess server. The arbiter can tell players whether they’ve made legal or illegal moves, when a capture occurs, what pawn captures are available, and from what direction their king is in check. The actual play is the same as standard chess, and so is the goal: checkmate.
