The final boss in Kirby 64: The Crystal Shards is 0², commonly pronounced “Zero Two.” It is the true final boss encountered after Kirby collects every Crystal Shard and unlocks the game's best ending.
0² is closely connected to Zero, the giant eye-shaped final boss from Kirby's Dream Land 3. In Kirby 64, the creature appears as a large spherical entity with a single eye and angelic wings. Its visual design and role establish it as a continuation or reinterpretation of the earlier Dark Matter leader.
A common mix-up is Miracle Matter, which is a major boss fought earlier in the game. Miracle Matter is not the final opponent. Nightmare is the principal antagonist of Kirby's Adventure and the Kirby anime, while Dark Matter is the broader enemy force driving the conflict in Kirby 64. The superscript-style name is often typed as 02, Zero Two, or Zero2, but 0² is the canonical presentation.