Ravenous Vampire {3}{B}{B}
Creature — Vampire
Flying
At the beginning of your upkeep, you may sacrifice a nonartifact creature. If you do, put a +1/+1 counter on this creature. If you don't, tap this creature.
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Devouring Sugarmaw // Have for Dinner 86%
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"At the beginning of your upkeep, you may sacrifice an artifact, enchantment, or token. If you don't, tap this creature."
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"At the beginning of your upkeep, you may sacrifice an artifact. If you don't, tap this creature and it deals 2 damage to you."
Primordial Ooze 84%
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"At the beginning of your upkeep, put a +1/+1 counter on this creature. Then you may pay {X}, where X is the number of +1/+1 counters on it. If you don't, tap this creature and it deals X damage to you."
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"At the beginning of your upkeep, tap this creature unless you sacrifice another creature."
Ravenous Demon // Archdemon of Greed 80%
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"At the beginning of your upkeep, sacrifice a Human. If you can't, tap this creature and it deals 9 damage to you."