Incite

Forced attacking is older than red's claim to it, but pricing the compulsion at a single mana and welding it to a color change is what makes this a fight-picker rather than a pure nuisance. The window is the turn you cast it: "attacks this turn if able" expires at end of turn, and a creature can only attack on its controller's turn, so the line is to cast this on your opponent's turn before their declare-attackers step, dragging one of their creatures into a swing it does not want to make and into a board you have already set against it. It does not stop the creature from blocking and it does not carry over, which means the trap has to be waiting when you spend the mana: a 1/1 compelled to attack into nothing pays you nothing. The red-until-end-of-turn clause reads like flavor stapling but does real work in a fight subtheme, turning an opposing white or green creature into a legal target for color-specific removal or feeding it to red damage-doubling. None of this cares about size or evasion, so the card is best understood as tempo dressed as removal-adjacent disruption: manufacture a bad attack, collect on the result, and let the cheap rate carry the rest. One successful line pays for the whole investment; the narrowness is that it asks you to build the punish before you ever cast it.