Ouroboros

Hexproof, Indestructible, reach
The power of ouroboros can't be more than zero.
Ouroboros can't receive counters.
You can cast one sorcery from your graveyard
per turn.
Whenever a criature leaves the battlefield,
you gain 1 life, and if theres no creature in
the battlefield, each player loses life equal the
number of creature cards in their graveyard