Fortress

A set of rules which can be played on any map showing political subdivisions. The players take turns placing one piece at a time on the mapboard in order to capture territories. Pieces may not be placed into enemy held spaces, and a player may not have more than three pieces in a single space. The diceless combat system requires you to establish a larger force in spaces adjacent to those occupied by the enemy. The game continues until both players pass, at which time the victor is the player who controls the most spaces.

The game was inspired by the 1983 SSI computer game Fortress, which was played on a 6x6 grid and limited to 21 turns.