Tri-Chess

Three player chess on a hexagonal board with two colors of hexagonal spaces (black and white).

There are six bishops (one per color for each player). The pieces have normal starting positions. The standard plastic chess pieces are ivory white, black and gold. There are eight pawns each.

Movement is somewhat complicated:

 The king and rook can move in 6 directions - onto adjacent hexes that share a side.
 The "diagonal" moves of the queen and bishop involve skipping over the two adjacent hexes of the other colours onto the hex beyond of the same colour. The bishop can thus move in 6 directions, the queen in 12.
 The knight can also moves onto 12 possible hexes - it moves two hexes forward and one to the side, always onto adjacent hexes that share a side.
 The pawn moves one diagonal hex forward and captures moving two adjacent hexes forward (these are the two hexes on either side of the one it could move to).

There are a few other special rules to deal with castling, pawn promotion and whether a diagonal move can pass between two occupied hexes.

Note that despite the identical name and designer, this game is not identical to Tri-Chess from 1975.