Edison Format · March 2010
This card can only negate trigger effects which specifically activate when a monster is Special Summoned.
It can negate the effects of cards like "Swap Frog", "Armageddon Knight", or "King Tiger Wanghu" (for all 3 examples, this card can only be activated when a monster is Special Summoned).
It cannot negate Ignition effects, even if activated with ignition Priority. It can never negate the effect of "Substitoad", "Dark Grepher", nor "D.D. Crow".
It cannot negate an effect which activated because a monster was Normal Summoned, even if that monster's effect states "if this card is Normal/Special Summoned".
① If a Monster Effect is triggered because a monster was Special Summoned: Negate the activation, and if you do, destroy the monster that activated that effect.