Sidisi, Undead Vizier is a rare Legendary Creature — Zombie Snake card from Dragons of Tarkir (DTK), collector number 120. Current market price: $10.24 (foil $19.08), TCGplayer market prices via Scryfall.
Deathtouch Exploit (When this creature enters, you may sacrifice a creature.) When Sidisi exploits a creature, you may search your library for a card, put it into your hand, then shuffle.