You can activate this card the turn it was Set, by revealing 1 Spellcaster monster in your hand. When a monster effect is activated in response to the card or effect activation of a card that mentions "Dark Magician": Negate that effect, and if you do, for the rest of this turn, negate the activated effects of monsters with that same original name. If you Special Summon "Dark Magician" while this card is in your GY (except during the Damage Step): You can pay 2500 LP; Set this card.