D/D Necro Slime (SP17-EN027) [Star Pack - Battle Royal]

If this card is in your Graveyard: You can Fusion Summon 1 "D/D/D" Fusion Monster from your Extra Deck, by banishing Fusion Materials listed on it from your Graveyard, including this card. You can only use this effect of "D/D Necro Slime" once per turn.