Relinquished

Ritual (Black Ritual. This card is Blue)
Defender, Limited 1
Once on your turn: you may tap and equip target creature an opponent controls. That creature
can't untap or be sacrificed until Relinquished
leaves the battlefield. If Relinquished would be
removed from the battlefield, exile one creature
equipped to Relinquished instead, then deal
damage equal to the exiled equipped card's
converted mana cost to it's owner.