|Game: Sonic Adventure / Sonic Adventure DX|
|Level: Station Square|
|Hits to defeat: 3|
|Fought by: Sonic|
|Next form: Chaos 2|
Chaos 0 is the first boss of Sonic Adventure. The game opens by throwing the player straight into the action, with this fight occurring before any tutorials, Action Stages or Adventure Fields. The opening cutscene shows Sonic casually sprinting along the sides of buildings in Station Square, until he spots squad cars of the S.S.P.D. tearing through the streets below. The hedgehog follows to find the police confronting this mysterious creature, who shrugs off the human's bullets in the courtyard outside City Hall. As the police turn tail and flee, Sonic steps in to take on the "big drip".
To begin with, Chaos simply shambles around the courtyard, periodically lunging at Sonic with his extendo-arms. After one homing attack hit to the brain he diversifies into a spinning-top move, and after the second hit he leaps high up on top of the flagpoles, punching down towards Sonic from out of range. Eventually he'll jump back down, where a third hit defeats him.
Chaos melts away into an aquamarine puddle and escapes down a grate into the sewer. Unseen by Sonic, Doctor Robotnik is watching from a rooftop high above, and seems very pleased with Chaos' performance.
SA2 character model