Scylla, Vortex Devourer

{b/g}{b/g}: Hydras you control gain deathtouch and
whenever this creature is dealt damage, put that
many +1/+1 counters on it until end of turn.
(It must survive the damage to get the counters.)
Scylla, Vortex Devourer enters the battlefield
with X +1/+1 counters on it.
When you cast this spell, create X X/X blue,
black, red, and green Hydra Leviathan creature
tokens.