Wyfroh, Northern Frost

Wyfroh, Northern Frost's power and is equal to
the amount of {s} sources on the battlefield.
If you don't control another snow creature when Wyfroh, Northern Frost enters the battlefield,
it's not a creature until your devotion to {u} is 6.
{3}{s}: When a snow creature enters the
battlefield, target creature you don't control
gets -2/-2 and can't attack or block until end
of turn. If that creature had power 4 or greater,
it can't attack or block permanently.