Neck Snap

White's clean kill spells have always paid a tax somewhere, because the color is not supposed to wield a no-questions-asked Doom Blade at any creature on the board. Here the tax is timing: the spell destroys anything regardless of color, type, or toughness, but only while the creature is committed to combat as an attacker or blocker. That restriction is what buys the unconditional destruction. The card forces you to leave mana open and answer at the one window when targeting is legal, which usually means holding up four during the opponent's combat rather than spending it on your own turn. It cannot be deployed proactively on a main phase the way most removal can, so it is reactive by construction: a creature is only a legal target while it is doing the single thing that makes creatures dangerous. The structural cousin is a combat trick that only fires once swords are crossed; this one skips the math and simply destroys, which is why it cuts down a high-toughness threat that a damage-based answer would chip at over several turns. The limitation that bites hardest is not the four-mana price but the word "destroy" itself: an indestructible attacker survives outright, while one carrying a regeneration shield lives too, though regenerating taps it and pulls it out of combat. So it answers size and stats cleanly while whiffing on the crop of creatures built to ignore destruction. Plain, behavior-gated white removal, legal to fire only at the moment of greatest threat.