Zhulodok, Void Gorger

Colorless spells you cast from your hand with
mana value 7 or greater have "Cascade, cascade."
(When you cast one, exile cards from the top
of your library until you exile a nonland card
that costs less. You may cast it without paying
its mana cost. Put the exiled cards on the bottom
in a random order. Then do it again.)
Yog-Sothoth is the key and guardian of the gate. Past, present, future, all are one in Yog-Sothoth.