Undead Reckoning

As an additional cost to cast this spell, exile X creature cards from your graveyard.
Amass Zombies X, then non-Zombie creatures
get -1/-1 until end of turn for each Zombie card
exiled with Undead Reckoning.
Whenever an Army you control deals combat
damage to a player, you may pay that much life.
If you do, return Undead Reckoning from your graveyard to your hand.