Skull Kid

When Skull Kid enters the battlefield, create a legendary black Aura enchantment token named
Majora's Mask and attach it to this permanent.
The token has enchant creature, shroud, and "Enchanted creature gets +5/+5 and has flying".
At the beginning of your upkeep, if Skull Kid is enchanted, put a dawn counter on Skull Kid. At
the beginning of your end step, if Skull Kid has
three or more dawn counters on it, destroy all permanents you don't control.