Troamor, Orazca Ancient

Delve (Each card you exile from your graveyard
while casting this spell pays for {1}.)
Whenever you cast an instant or sorcery spell
from your hand, you may cast an instant or
sorcery spell exiled to cast Troamor, Orazca
Ancient without paying it's mana cost. Put that
spell on the bottom of your library after it
resolves.