Crimson Hellkite

The body lands as a 6/6 flier, respectable for its era, but the dragon is really a delivery vehicle for a tap ability that scales as large as your red sources allow: point X damage at any creature, then do it again next turn. The clause doing all the balancing work is the one most players skim past, the requirement that X be paid only with red mana. That single restriction stops the card from becoming a colorless ramp engine any deck could abuse with artifact mana; it demands a mono-red or red-heavy manabase, and pays out exactly on the mountain-flooded board a big-red deck wants to build anyway. The targeting matters too: creature-only, never "any target," so this is a recurring removal turret rather than a reach-to-the-face finisher. You will grind down the biggest threat on the battlefield, but you will not burn an opponent out with it. That places the card in a small family of expensive red dragons that double as repeatable creature removal, a space later explored from other angles by Balefire Dragon and Hellkite Tyrant. What sets this earlier version apart is how undivided it is: the dragon and the cannon occupy the same card, with no death triggers, no combat-damage conditions, and no second mode. The only variable is how much red mana you can pour into the activation, and the body that holds the cannon happens to fly over the blockers it cannot be bothered to shoot.