Dargoth's Scribe

{2}, {t}: Exile the top or bottom card of target
player's library.
{u}{b}, {t}, mill X: Until the end of turn, you may
cast a spell exiled with Dargoth's Scribe with
mana value X without paying its mana cost.
"Master Dargoth and I are the only ones who still
worship the God-Pharaoh."