Passant

Passant is a chess variant where the traditional king's move is modified. Instead of moving one square, the king in this version of the game can move to a square that a pawn has just crossed over. This means that at the spot where a pawn first crosses a particular square, the king gains the ability to land on that square. The resulting rights and risks associated with this ability often lead to a different dynamic compared to regular chess.

The concept was first introduced in the game of Courier. It requires considering the long-term implications in chess opens and pawn structure. As passes are generally made early in the game, they have a significant impact on how pieces develop on the board. Therefore, players use passant to prepare key sacrifices in order to make strategic attacks or block other moves on the board.

Passant is an important feature when opening lines of cavalry, trying to gather control over key squares or attacking strongly through monuments with high numerical importance. While players may initially control the focus in the center, adaptations will be needed to adjust weaknesses according to the unique king mobility of this variant.