Sidequest: Play Blitzball // World Champion, Celestial Weapon

The unlock condition is the entire design. The front face reads as a sluggish combat enchantment, handing a modest +2/+0 to one of your creatures as combat opens while quietly tallying the damage you push through. Connect for six or more combat damage in a single turn and it flips at end of combat into a Celestial Weapon, then staples itself onto one of your creatures for free. That transform is one-way and terminal: once the enchantment becomes an Equipment, the six-damage threshold is gone, replaced by a permanent +2/+0 and double strike that no longer cares how hard you connect. The starting pump exists only to help clear the gate once; after that, the weapon is a trophy, not a renewable engine. The Equip cost matters only after the weapon has fallen off or when you want to move it to another creature, and that is the sequencing wrinkle worth noting: the initial attach is free and reactive, triggered off a combat you already won, while re-equipping later is a sorcery-speed investment. What sells it is theme fidelity. Blitzball as a sidequest is a grind you slog through until it coughs up the game's best equipment, and the card models that arc in its mechanics: labor first (a big turn of combat damage), then a reward that trivializes everything after. The design asks you to be the beatdown, then hands you a payoff for having been the beatdown, an aggressive reward dressed as a two-sided flavor set piece.