Joust Through

The restriction is the whole design conversation: three damage for a single white mana is generous, but only against a creature already committed to combat. That clause converts a would-be premium burn spell into a purely reactive tool, one that does nothing in your own main phase and cannot preempt a threat before it swings. White has long paid for its removal with exactly this kind of timing tax, forcing the card into the narrow window where an opponent has already chosen to attack or block. The upside is that combat is where creatures overextend, and three damage cleanly answers most of what walks into a red zone at instant speed. The incidental life gain rounds it toward the attrition role white removal tends to occupy, tilting close damage races and rewarding the defensive posture the targeting requirement already imposes. It is a study in giving a color efficient removal without giving it the flexibility that efficiency usually implies: the mana is cheap because the timing is expensive.