Eriette of the Steep Sleep

Sacrifice an Enchantment: Ward 3 until end of turn.

Whenever an enchantment enters under your control, place a Stun counter on a target creature.
(If a permanent with a stun counter on it would become untapped, remove a stun counter instead.)

{3}{w}{u}{b}: Gain control of target creature with three or more Stun counters on it for as long as Eriette remains on the battlefield.