Mercurial Geists (EMN)

Creature — Spirit

Flying Whenever you cast an instant or sorcery spell, this creature gets +3/+0 until end of turn.

Reliable threat for UR spellslinger decks in Pioneer and Modern. Mercurial Geists turns every instant and sorcery into a burst of damage while eluding ground-based blockers, making it a natural fit for tempo and prowess-adjacent strategies. The +3/+0 pump scales well with cantrips and interaction, turning a modest flyer into a clock that pressures opponents before they stabilize. Best in decks already built around casting multiple spells per turn; less impressive in slower shells where it's just a 2/2.

Eldritch Moon — Uncommon