Finally, a Chess variant board has been developed that accommodates three players, without compromising ANY of the rules, strategies, or competitive challenges that make Chess the best board game in the world. The only changes from conventional chess are some protocol issues that must be followed to maintain order where the teams border each other, which is simple and necessary.
Also, please notice that the trajectory lines orienting from the outer rank, are simply visual aids to help guide diagonal moves passing through the center. If the path is clear, a diagonal move starting from the outer rank can pass through the center and sweep back around to where it originated. The complexities of the third player are infinite. Your threatened piece may be allowed to maintain occupancy as your position is beneficial to the threatening player. But how long can it last? This scenario may exist all over the board. There are multiple trust and doubt situations between all players. An unexpected move might well result in a cascading massacre. Defense is crucial since a diagonal move through the center, or a horizontal move around the center can sneak up behind you. A player can be checkmated by a combination of both other players or ultimately one player can checkmate both other players at the same time.
Rules of the game here