Wall of Opposition

Five mana for a 0/6 wall with firebreathing is a design from the era when red's relationship with defense was still being negotiated. Red walls existed almost exclusively to stop creatures from getting through; this one bends the template by letting you spend mana to push damage on the counterattack, except the counterattack is impossible because defender locks the door. The pump ability exists to make blocks lethal, not to threaten lethal across the table. That is the joke and the limitation: you sink mana into a 0/6 to turn it into a 4/6 or 5/6 blocker that trades up, and the card's ceiling is bounded by how much mana you have open on your opponent's attack step. Legends was full of these stat-line curiosities, creatures priced on raw toughness with a single repeatable ability bolted on, and the firebreathing here is the plainest version of the idea: generic, incremental, useful only on the defensive side of combat. The contemporary red walls share the same shape, a defender with a pump that can only ever matter when blocking. None of them found a home, because the format quickly decided that five mana for a blocker, however large, was not where red wanted to spend its turn. The card survives now as a flavor piece and a snapshot of how cautiously early designers built around toughness as a resource.