Demonic Dealing

Jolt {b}{b} (You may cast this spell for its jolt cost. If
you do, exile it after it resolves and it deals 3 damage
to you)
Exile cards from the top of your library until you
exile a nonland card, you may cast that card
without paying its mana cost. If you do, repeat
this process. You lose life equal to the total
converted mana cost of each spell you cast this
way. If Demonic Dealing's jolt cost was payed,
you lose twice that much life instead.