Gruff is a tactical "Expandable Card Game" about mutated monster goats. Players create a customized team of monster goats called "Gruffs" led by a shepherd. You win the game by crushing through the enemy line of gruffs and killing the opposing shepherd.

Players take turns playing ability cards and declaring attacks. After an attack is declared your opponent takes his turn and may dodge or block your attack then declare his own attack. Your attack resolves at the beginning of next turn.