*In the 1998 video game Sonic Adventure, Chaos 0 is a monster that Dr. Ivo Robotnik releases from the Master Emerald:

Chaos 0 appears Chaos 0 stands on top of City Hall, absorbs police bullets, and jumps off the building.

Sonic fights Chaos 0 Sonic jumps into the action and quickly defeats Chaos 0, leaving it as a puddle.

Chaos 0 escapes Chaos 0 makes its way into a sewer manhole and escapes.

Chaos 0's plan Chaos 0's plan is to use Chaos Zero to destroy Station Square and build "Robotnikland".

In Sonic Adventure, Sonic and Tails must collect the Chaos Emeralds before Eggman can use them to power Chaos, an angry water creature. Knuckles is trying to repair the Master Emerald, and Amy must avoid capture from an Eggman robot.*