Glacial Hydra

When Glacial Hydra enters the battlefield, put a
+1/+1 counter on it for each {s} spent to cast it.
Whenever Glacial Hydra is blocked by a non-
snow creature or becomes the target of a non-
snow spell or effect, put a +1/+1 counter on it.
These remarkable creatures have evolved fierce
defenses against things not native to their polar
environment.