Three Man Chess takes the game to a whole new level by adding an additional player. All of the rules remain the same, but strategy gets a makeover once players find themselves in trust and doubt situations, trying to figure out who the current target is. Defense becomes critical, as a move into the center puts you at risk on multiple fronts. And checkmate becomes even more unpredictable, with a player being checkmated by a combination of the other two players, or two players being checkmated at the same time by the third player.
Even Grandmaster Bobby Fischer would find this challenging.