Zhaitan, The First Hydra.

Exempt(This creature cannot be exiled)
Whenever Zhaitan, First Hydra is dealt damage, you may discard a card. If you do, put two +1/+1 counters on it.
At the beginning of your upkeep, if Zhaitan, First Hydra has more than ten +1/+1 counters on it, you may remove all counters from it. If you do, create a nonlegendary 1/1 token copy of Zhaitan, First Hydra.