Merseine (Fallen Empires)

Enchantment — Aura - Enchant creature
This Aura enters with three net counters on it.
Enchanted creature doesn't untap during its controller's untap step if this Aura has a net counter on it.
Pay enchanted creature's mana cost: Remove a net counter from this Aura. Only the controller of the enchanted creature may activate this ability.