Krosis, General of Apocrypha

Shroud, Hexproof, Lifelink
Whenever you cast a spell create a 2/2 black
Zombie creature token and amass 1.
When a creature you control dies, you gain 1 life
and opponents lose 1 life.
If Krosis, General of Apocrypha dies or is exiled, shuffle it into your library instead.