Matter and Antimatter is an abstract strategy game played on a square board with a square grid; suggested board sizes are 8x8 and 18x18, rhough others can be used. Each player has enough pieces to fill the two rows nearest them at the start.
On their turn a players rolls dice, with the number being scaled to the board size; one die is suggested for the 8x8 board and three for the 18x18 board. The roll determines the number of moves that can be made; a piece can move to any of the five adjacent squares ahead or to the side of it. However, pieces can be moved on top of friendly pieces and a stack of pieces costs as many moves to go one space as the number of pieces in it.
A stack can only be moved onto an opposing stack if the latter is smaller; in this case the entire opposing stack is removed as well as an equal number of pieces from the moving stack.
The game ends when a player cannot make any possible move (in which case their opponent wins) or a player has advanced all their pieces to the other side of the board (in which case they win).
The game was first published in World Game Review #2.
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