Smite the Monstrous

The whole design conversation lives in that power-4 threshold. Pinning the line there means the spell cleanly answers the fatties (dragons, demons, the beater wearing a pile of auras) while leaving the entire low end of the curve untouched, and that asymmetry is the point. This is a recurring template white reaches for when the goal is removal that punishes greed without trivializing the early game: you get to deal with the monster, not the menace. The trouble is the seam in the middle. A format's most dangerous threats are often its cheapest, and a 3/3 or a 2/2 with an engine bolted on sails right under the power line. Four mana is a steep ask for a spell that cannot touch most of the board, and the power rider is what white pays for keeping the cost up rather than handing aggressive decks a premium-rate answer; this is deliberately the expensive, restricted version of a kill spell, not white's clean unconditional removal. What partly redeems the rate is instant speed. You can let the big threat resolve, let your opponent commit to the attack, and answer it after blocks, turning a plain destroy effect into a combat-step ambush that takes the creature and the swing in one beat. It is a narrow, costly tool by design: the price is the brake on a destroy effect that would otherwise be too easy to point at anything.