Cyball is the boss of the cyberspace level of Mega Man Zero 4. It consists mainly of four energy shooters, two platforms and a glowing sphere (which is also the weak point). It can use Cyber elves and protects the Teleporter Circuit. Zero has to destroy it to be able to teleport to Ragnarok.
- It floats toward the player and around the platforms, in a figure 8-like pattern.
- It creates three globs and sends them toward the player. One can beat these globs back until they disappear.
- It creates an electrical field around the borders of the room. As long as Zero is on the first platform he won't get hit.
- Cyball splits into four smaller spheres that spin around in a circle as it approaches Zero and crosses the room. It is invincible from attack while doing this, and can be dodged by jumping carefully
- EX Skill: When faced at A-Rank or higher, Cyball's core turns pink, and fires laser blasts straight ahead, while the two energy shooters on the side of the room it stopped on also turn pink and fire additional laser blasts. These blasts can be dodged with precise jumping from platform to platform.