Coronafection

Enchant tapped creature
Enchanted creature has "At the beginning of
your upkeep, put a -1/-1 counter on enchanted
creature, then attach Coronafection to another
creature you control without -1/-1 counters. If
you cannot, you get a poison counter for each
creature you control with a -1/-1 counter, and
then sacrifice Coronafection."

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