Viktor, Bloodlust Tyrant

Eminence — Whenever a creature an opponent
controls dies, as long as Viktor, Bloodlust Tyrant
is in the command zone or on the battlefield,
create a blood token. If you control twenty blood
tokens, Vampires you control gain Annihilator 1.
Lifelink, deathtouch
{b}{r}{t}, Sacrifice X blood tokens: Search your
library for a creature with X converted mana
cost, put it on top of your library, then shuffle.
You lose X life.