Mario & Sonic at the Olympic Winter Games
Thousands of years ago, the leader of the Knuckles Tribe, Pachacamac decided to attack Chaos as well as the Chao it was protecting. Pachacamac also attempted to steal all of the Chaos Emeralds. Due to his actions, Chaos became enraged and transformed, for the first time, into his perfect state using the Chaos Emeralds negative energy and wiped out the majority of the Knuckles Tribe. The destructive creature was still filled with anger afterwards, and decided to continue attacking the rest of the world. Tikal decided that the only way to stop Chaos was to use her prayer to seal him, as well as herself into the Master Emerald.
 Game Appearances
 Sonic Adventure
After deciphering ancient echidna writings, Dr. Eggman successfully freed Chaos from the Master Emerald to use as a weapon. Eggman decided to search for the Chaos Emeralds in order to transform the creature into Perfect Chaos once more, making it invincible. Chaos eventually rebelled against Eggman and took all seven Chaos Emeralds for himself and used them to become Perfect Chaos. As a result, Sonic uses the positive energy of the emeralds to become Super Sonic.
This final boss battle takes place in Station Square, which is now flooded and destroyed. Super Sonic must make his way through the flooded city and its wreckage, as well as collect rings along the way, since he need rings to remain in his Super Sonic state. Super Sonic starts off with 50 rings, and once the ring count drains to zero, it will cost him a life.
To damage Perfect Chaos, Super Sonic must gain enough speed to rush his way inside Perfect Chaos, in order to strike its brain. As Super Sonic approaches the creature, Perfect Chaos will attempt to slow down Super Sonic by launching attacks such as twisters and laser beams. As you damage him, Perfect Chaos attacks will become more aggressive. Attack the creature 6 times to defeat it and complete Sonic Adventure.
 Mario & Sonic at the Olympic Winter Games
In Mario & Sonic at the Olympic Winter Games, Perfect Chaos makes a cameo as an ice sculpture in the Dream Figure Skating Event(Sonic's World). While figure skating, players attack the creature by jumping on the creature when they are prompted.
 Sonic Generations
Perfect Chaos appears in Sonic Generations as the boss of the Dreamcast Era. In this version, players use Sonic, rather than Super Sonic in the original game. Sonic must simply boost while he's on the water, making his way through the flooded city and he will be fast enough to run inside Perfect Chaos and attack its brain. For the second hit, Sonic must use the platforms to make his way to higher ground while avoiding the creature's tentacles, then strike it's brain with the Homing Attack. As for the third hit, it plays out similarly to how you hit him the first time. With the final hit, Perfect Chaos causes the platforms to rise temporarily. Therefore, Sonic must quickly make his way through the floating platforms and strike Perfect Chaos one last time to defeat it.
 Other Appearances
 Sonic X
Perfect Chaos also makes an appearance as a villain in the animated series Sonic X, which had an arc that was adapting the Sonic Adventure story line. The creature's looks resembles his game appearances.
He has attacks similar to his game counterpart, but in the animated series, he also has a barrier, which prevents projectiles from harming it. As with Sonic Adventure, Sonic transforms into Super Sonic and easily defeats Perfect Chaos after dealing damage to the creature's brain.
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