Margit, the Fell Omen

When Margit, the Fell Omen enters the battlefield, you take the initiative.

At the beginning of each opponent's upkeep, untap
a creature you control. If you've completed a
dungeon, untap all creatures you control instead.

"Foul Tarnished, In search of the Elden Ring. Emboldened by the flame of ambition. Someone must extinguish thy flame. Let it be Margit the Fell!"