In play is the official name of situation of units in the battle area. Only those units in the battle area can participate in battle cycles. In play units will die if health reachs 0 and be sent to graveyard. Units, artifacts and spells enter the field by reaching zero ready value in staging area or the reanimate spell. Various resurrection abilities are aimed to place units in graveyard back into the field. When all units of one side are not in play, that does not mean an immediate defeat. Instead no battle cycles occur for that side but ready value of cards in staging area still decrease.