Shiny Black "C" (Blue) (DL14-EN007) - Duelist League Promo Unlimited Rarity_Shatterfoil Rare otherwise negate the activation of

otherwise negate the activation of their Spell Card

TypeDragon / Synchro / Effect Monster

and banish all cards with that monster's name from both Decks

You can only use this effect of “Sinister Serpent” once per turn

Shiny Black "C" (Blue) (DL14-EN007) - Duelist League Promo Unlimited Rarity_Shatterfoil Rare otherwise negate the activation ofTypeInsect Effect Monster AttributeEARTH Level Rank1 ATK DEF200 500 Card TextDuring either player's turn, when exactly 1 Synchro Monster is Special Summoned to your opponent's side of the field: You can banish this card from your Graveyard to target that face up Synchro Monster; destroy that target.