Lady Loki, Agent of Chaos
Most impulse-payoffs hand you a card off your deck and call it a reward. This one pays you in the distance between two mana values: when the once-per-turn trigger fires, the spell you cast is exiled, cards peel away until a nonland turns up, and the gap between those two mana values becomes damage to each opponent. That inverts the usual incentive. A cheap trigger digging into an expensive flip does far more damage than a matched pairing, so the deck wants a curve with real spread rather than a smooth ramp: the burn cares about mismatch, not quality. Lands passed over along the way never enter the math, so a flooded run costs you nothing but the tempo of digging deeper, and the nonland you eventually reach you may cast for free (the original spell is gone, not recast). Folding the Villain type into the trigger alongside instants and sorceries is the clever part: it lets a creature-based build feed the same engine rather than stranding it outside a spellslinger payoff. The result reads as a clock more than a value piece, a harder register for a red six-drop to reach, and the single-trigger-per-turn gate keeps the variance from compounding. You get one high-leverage cast to sequence around each turn, not a chain that snowballs on itself.
