Nekroz of Unicore

You can Ritual Summon this card with any "Nekroz" Ritual Spell. Must be Ritual Summoned and not special Summoned by other ways. 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.