Fracture

Three noncreature categories, one two-mana instant, and the color pair that has to marry two identities to reach all of them. Neither color gets there alone: white handles artifacts and enchantments but cannot reliably kill a planeswalker, black murders walkers but can't touch metal. Splicing the pies together is what buys coverage a mono-colored answer would have to overprice. That breadth cures the usual disease of a hoser, the dead card against a board without the right target: a battlefield holding no artifact, no enchantment, and no planeswalker is uncommon enough that the answer seldom rots in hand. Creatures and lands stay off the list, and that omission is precisely what keeps the price honest and the effect a rung below a two-color Vindicate. The instant speed does not let it snipe a planeswalker before the loyalty ability worth killing has resolved; the controller holds priority and activates first. What the speed grants is patience: hold the answer in reserve, respond to a permanent the turn it threatens to snowball, and detonate an artifact engine during the opponent's own turn before it dominates the next one, rather than tapping out for a sorcery and forfeiting the right to react. The card is a study in what a guild pair unlocks that neither half owns: not a new effect, but a wider net at a price mono-color can't match.