Spreading Mildew
Type: Evil Enh. • Brigade: Gold • Ability: None • Class: None • Special Ability: Place on a Fortress in play. Negate the special ability on that Fortress. All cards in that Fortress are returned to owner’s hand. After four turns, discard this card to discard that Fortress.
OK,
I place SM on a fort. 4 turns pass, but I don't want to discard the fortress. So does SM stay on the fort basically negating it the rest of the game? How does this work?
Thanks!