Skyhunter Cub

Naked, this is a 2/2 with no abilities, an easy trade for almost anything. The conditional clause is the entire pitch: bolt any piece of equipment onto it and the Cub gets +1/+1 and flying, turning a vanilla body into a 3/3 evasive threat. The design pushes the card's rate out of its mana cost and into whatever gear it carries, which means it scales with the weapon. Stack a Bonesplitter's +2/+0 on the Cub's own +1/+1 for a 5/3 flier; a Leonin Scimitar makes it a 4/4 in the air. The reward is symmetrical to the risk, though: remove the equipment or the Cub never gets off the ground, and you are back to a body that does nothing. This is the equipment-creature template at its most honest, a flier whose evasion and bonus stats are entirely outsourced rather than printed on the card itself. The lineage that followed refined the idea (creatures that care about equipment in subtler ways, equip-cost reducers, living weapons that supply their own body), but the Cub states the bargain bluntly: it flies only while it is armed, and it is exactly as good as the steel you hand it.