I recently put Stalks of Flax in a deck, and I was wondering, if I exchange a unique character, say David with an opponent's character (it doesn't really matter who) and then I put down another David and he stays around until Stalks of Flax is done, what happens when my David attempts to return to my territory?
Stalks of Flax (TP)
Type: Artifact • Special Ability: On activation, discard this card to exchange two O.T. human Heroes in your territory with two Heroes in an opponent's territory for two turns.