Lemurian Zigguraplaex

As Lemurian Zigguraplaex enters the battlefield,
you may pay Insanity {3}. If you don't, it enters
the battlefield tapped. (Insanity is a cost. To pay
Insanity 3, shuffle your library, then exile the top
3 cards.)
{t}: Add {u} or {c}.
Long ago before the seas whelmede small things
fled the very presence of that which dwelt there.