Blight Stone Ring

Equipped creature has Infect
Equip {3} ({3}: Attach to target creature you control.
Equip only as a sorcery.)
Lock (Equipment cannot be removed from equipped creature.)
When Blight Stone Ring becomes equipped to to creature put 3 countdown counters on equipped creature at the beginning of your upkeep remove
a counter. When there is no more counters
sacrifice equipped creature.