Pentaplane is a three-dimensional board (five stacked 5x5 square grids) on which several games can be played: Pentaplane-Aircraft. A "rudimentary" game (the designer's word) in which each player controls a single piece representing an airplane and attempts to shoot down the opponent. Moves are plotted in groups of five. The planes move the same as the rooks do in the later games. Pentaplane-Checkers. This is played much like standard checkers, but the pieces move diagonally between boards, not on the same board. Some spaces on the boards have dots to facilitate diagonal movement, which is always from dot to dot or blank to blank. Pentaplane-Chess. This has a number of differences from standard Chess besides the board. There are no kings of queens, instead there are monarchs, and they can only be obtained by promoting pawns. Pawns can move backwards as well as forwards. The bishops move the same way as the pieces in Pentaplane-Checkers. Super Pentaplane-Chess. Pentaplane-Chess but with a much greater variety of pieces: a president which can move along flat diagonals, a hopper which must jump over another piece when moving, missile versions of pieces which can destroy other pieces at a distance, bomb versions of pieces which can blow up and destroy a 3x3x3 area, etc. Players agree on which pieces are allowed before the game. They do not have to use the same set of pieces. Note that the new pieces introduced here are not included in the Pentaplane set. Pentaplane V. This game is not included in the rulebook, but is available online (see the Links section). This is a modified version of Super Pentaplane-Chess with some differences in the list of pieces.