Irithyl of the Boreal Valley

Whenever you cast your first noncreature spell each
turn, put a deep counter on Irithyl of the Boreal
Valley.
{1}, {t}: Add {c}{u}. Activate only if you've cast a
noncreature spell this turn.
{4}, {t}, Remove a deep counter from Irithyl of the
Boreal Valley: Create a 4/3 blue and black Beast
Horror creature token with menace.