Tiles are printed on one side only, so you can see them but your opponent cannot. Much of the game is decided before any moves actually take place, since you can arrange your 40 tiles in any configuration you desire on your 4 x 10 section of the playing board.
Each player can move one tile per turn. If a tile is moved onto a square occupied by an opposing tile, their identities are revealed; and the weakest tile is removed from the board. Ties result in both tiles being removed.
For most tiles, the rank alone determines the outcome, but there are special tiles such as Bombs (which only Miners can defuse, but are unable to move) and a Spy (which wins an attack against the highest ranked tile, the Marshal, but loses when attacked by any piece, including the Marshal). From highest rank to lowest the movable tiles are: Marshal, General, Colonel, Major, Captain, Lieutenant, Sergeant, Miner, Scout, Spy. The immovable tiles are the Bomb and the Flag.
The object of the game is to find and capture the opponents flag piece.
The game was invented by the Milton Bradley Company, and first published in 1961 (although it was trademarked in 1960). Tiles were originally made of painted wood, but later in editions they are plastic.