|This character exists primarily or exclusively within the Sonic X anime or comic continuity.|
Information in this article may not be canonical to the storyline of the games or any other Sonic continuity.
Genderless (referred to as male)
|Alignment and character traits|
|Skills, abilities and powers|
Chaos was the guardian of the Chao that lived near Master Emerald several thousands of years ago. Then one day, Tikal's father, Pachacamac, tried to take the seven Chaos Emeralds so that they had the power to defeat their enemies. As they charged through the shrine, they harmed the Chao and Tikal. Chaos, enraged by seeing his friends hurt, transformed into a terrifying monster which killed all of them and was imprisoned in the Master Emerald by Tikal before his rage could wreck more havoc.
Chaos was imprisoned by the Master Emerald for several years, until Doctor Eggman destroyed it and set Chaos free. A piece of Chaos was subtracted and swallowed by Froggy, who stole the Purple Chaos Emerald. Later, he sees Cheese, and Chaos attacked Station Square and was fed the Yellow and Red Chaos Emeralds by Dr. Eggman. After being defeated by Sonic and Knuckles, it left.
Later, Sonic and Tails found the Cyan and Green Chaos Emeralds, but Chaos 2 swallowed them up too, becoming Chaos 4. He was recalled by Eggman and then ate Christopher Thorndyke, Big, Froggy and Lily's Blue Chaos Emerald, becoming Chaos 6. Knuckles and Sonic defeated him, but in episode 31, he attacked Eggman and then absorbed the White Chaos Emerald in the following episode, becoming Perfect Chaos. Chaos then destroyed and flooded Station Square, scattered all the Chaos Emeralds in numerous directions, drained of their negative power but they were gathered by Amy, Cream, Chris, Big, Knuckles and Eggman. Sonic harnessed their positive energies to become Super Sonic and defeated Perfect Chaos. After he returned to Chaos 0, Tikal took him home.
Chaos 0 was Chaos' true form. He used it to destroy Tikal's father, and also in Station Square until Eggman fed him the Yellow Chaos Emerald, transforming him into Chaos 1. He later took this form again when Perfect Chaos was defeated and he regained his sanity.
Chaos 1 was the first form Chaos took. He fought Sonic and Knuckles until Eggman fed him the Red Chaos Emerald, transforming him into Chaos 2.
This was the second form Chaos took, until Sonic and Knuckles defeated him. Eggman then recalled him. He later absorbed the Cyan and Green Chaos Emeralds, transforming into Chaos 4.
Chaos took this form when Tails dropped the Green and Cyan Chaos Emeralds, becoming Chaos 4. He then battled Tails and Sonic until Eggman recalled him. He later absorbed the Purple and Blue Chaos Emeralds, becoming Chaos 6.
This was the fourth form Chaos took, when he absorbed the Purple and Blue Chaos Emeralds. He nearly defeated Sonic and trapped Big, Froggy and Chris, until Knuckles came by and helped Sonic destroyed Chaos 6's brain and defeated him. However, he survived and later attacked Dr. Eggman, taking the White Chaos Emerald and becoming Perfect Chaos.
This was Chaos' final and strongest form. He absorbed the White Chaos Emerald and became Perfect Chaos, flooding Station Square. He let all the Chaos Emeralds go and were gathered by Sonic's friends, and their friendship helped restore the Emeralds' power. This allowed Sonic to become Super Sonic and defeat Perfect Chaos, returning him to Chaos 0.