Skull Kid, Majora’s Vessel

Hexproof
Majora's Mask — Skull Kid, Majora's Vessel
enters the battlefield with three Moon counters
on it.
Clocktown's Doom — At the beginning of your
upkeep, remove a Moon counter from Skull Kid, Majora's Vessel. Then, if there are no Moon
counters on it, each opponent loses the game.