If this card was Set by the effect of an "Altergeist" card, you can activate it the turn it was Set. When this card is activated: Send 1 "Altergeist" monster from your hand to the GY. When your opponent activates a Trap Card (except during the Damage Step): You can send 1 "Altergeist" monster from your hand to the GY; negate that effect, and if you do, destroy that card. You can only use each effect of "Altergeist Haunted Rock" once per turn.