Teneb, Grim Patriarch

Whenever a terror creature you control attacks, if defending player controls a Swamp, that creature gets a +1/+1 counter and gains wither until end of turn. (Horrors, Nightmares, Scarecrows, Skeletons, Spirits, Vampires, Werewolves, and Zombies are terrors.)

{6}, Sacrifice a terror creature you control: Proliferate X times, where X is equal to the sacrificed creature's converted mana cost plus 1, then draw a number of cards equal to Teneb, Grim Patriarch's power.

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