The Flood
0/0 Black Curse
-X=Number of cards discarded from your deck-
"Negate Healing this turn. Discard your deck, territory and set-aside area (except Lost Souls) regardless of protection to Discard up to X of opponents' cards in play or set aside regardless of protection. Cannot be Negated."
A curse because, even though it was sent by God, it was a punishment (making it a good card makes no sense). Black because the only Evil antediluvian is Black. Basically, you lose everything except what's in your hand (which, conveniently, holds the exact number of people that were on the Ark when you're defending) and wipe out your opponent's territory (and win the block if you play it as an Enhancement). You can't weasel out of the cost by being decked because then it won't do anything.