You can Ritual Summon this card with any Nekroz Ritual Spell. Must be Ritual Summoned. You can discard this card, then target 1 Nekroz card in your GY, except Nekroz of Unicore ; add it to your hand. You can only use this effect of Nekroz of Unicore once per turn. Negate the effects of face-up monsters on the field that were Special Summoned from the Extra Deck.