Draconic Hydra

Draconic Hydra enters the battlefield with X
head counters on it.
Draconic Hydra has +1/+1 for each head
counter on it.
Whenever Draconic Hydra is dealt damage
prevent it and remove a head counter from it,
or you may pay {r}{g}{g} instead and put a
head counter on Draconic Hydra.