Tessen is a card game featuring simultaneous real time play. Players take animal cards from their decks and play them in up to five groups in front of them. Players may save sets of three or more, but beware! The opponent may use a warrior card to "attack" forcing the player to give up the attacked animal cards. The attacking player may then take the cards for his own. Also, warriors may be used to "defend" and nullify an opponent's warrior.