Arrows of Justice

The condition on the targeting is the whole pitch: four damage clears almost anything a creature deck plays, but only while that creature is committed to combat. That restriction turns a removal spell into a combat trick run in reverse, a punish aimed at the player who already declared the attack or block and can no longer back out. The window matters more than the rate. Against a defensive opponent who never swings and blocks only when forced, the card sits dead in hand until they finally have to commit a body; against an aggressor it ambushes at the most expensive possible moment, after the attack step is already spent, and trades one-for-one on terms the opponent chose and now cannot unchoose. The Boros hybrid cost does the second piece of work, letting either color foot the bill and keeping the card legal in any deck that wants to play to the combat phase rather than around it. Compared with a no-strings burn spell, the discount you pay for the restriction buys an extra point of damage in exchange for surrendering the freedom to fire whenever you like: this one waits for combat or it does nothing. It is a removal spell built for the player who holds up mana and lets the opponent make the first aggressive decision, then makes that decision cost them.