Magus of Throes

Cascade (When you cast this spell, 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 of your library in a random order.)
Retrace (You may cast this card from your
graveyard by discarding a land card in addition to
paying its other costs.)
Endless power, endless pain.