Raging Spirit

Pay two mana and this Spirit sheds its color until end of turn, and that single line is the entire reason the card exists. It comes from a moment when color was a live board-state property rather than just a deckbuilding constraint, when protection-from-color and color-hosed effects were a recurring theme and spending mana to dodge them counted as a real tactical maneuver. The dodge works both directions. On offense, turning colorless doesn't let the attacker slip past a blocker with protection from red (that creature can still legally block); what changes is that its damage-prevention against red no longer applies, so the block stops working the way the defender wanted. On defense, a colorless body shrugs off removal that only bites red creatures and can profitably trade with attackers a red creature could not. But it only ever matters against a specific subset of opposing cards; against everything else the ability is dead text, and the transformation does nothing on a clear board. The body is the problem. Four mana buys far too little for an answer that activates only after the opponent has already assembled the precise threat it solves. This reads now as answer-to-an-answer design: a creature priced to beat a metagame assumption rather than to do anything proactive, built back when players still expected to maindeck their hedges against color hate. That assumption has long since left the game, and without it the card has nowhere to point its ability.