D/D Necro Slime

[ Fiend / Effect ] If this card is in your GY: You can Fusion Summon 1 "D/D/D" Fusion Monster from your Extra Deck, by banishing Fusion Materials mentioned on it from your GY, including this card. You can only use this effect of "D/D Necro Slime" once per turn. ATK/ 300 DEF/ 300