Chaos 0

Chaos as he appears in Sonic Adventure 2.

Chaos (Kaosu) is a fictional character in the Sonic the Hedgehog series and the main antagonist in the video game Sonic Adventure for the Sega Dreamcast. Chaos is an immortal, ageless god-like creature that seems to be composed entirely of water (ironically, Sonic has a weakness of water), but is also said to be concentrated Chaos Emerald energy (in Sonic X, Doctor Eggman implies that it is composed of "Chaos energy in a liquid state"); it is really a mutant Chao. It was trapped inside the Master Emerald for thousands of years before being released by Dr. Eggman in a bid to conquer the world. It was also the original guardian of the Chaos Emeralds, Chao, and the Master Emerald. In Sonic Adventure, it absorbed the negative energy of the Chaos Emeralds to attain its final and strongest form.



Chaos was originally a good natured Chao. Contact with the positive energy of the Chaos Emeralds transformed it into a water-like creature. It used the power to guarantee clear water around the altar of the Master Emerald, and to protect its fellow Chao. However, the leader of the Echidna tribe, Pachacamac, tried to steal the Emeralds so he could use them against his enemies. His warriors stormed the shrine where the Emeralds were, harming many Chao in the process. Chaos, in a fit of rage, absorbed the negative power of the Chaos Emeralds, and transformed into Perfect Chaos. The resulting floods destroyed the civilization. Pachacamac's daughter, Tikal, linked her consciousness with Chaos's via prayer, and sealed them both into the Master Emerald. It is from this point in history that the emeralds were called "Chaos Emeralds". Nobody knows what happened to the Emeralds afterwards.

Sonic AdventureEdit

Chaos lay in wait for many centuries until Dr. Eggman, having read ancient tablets describing the fall of the Echidnas and Chaos, released it by shattering the Master Emerald. Chaos swears to follow Doctor Eggman as it knows that he can get the Chaos Emeralds back for it.

Eventually, Eggman's plans, as always, fell through at the hands of Sonic the Hedgehog and his friends. So Chaos abandoned him and collected the Emeralds itself. Once they were in its possession, it absorbed the negative powers of the Emeralds and transformed into Perfect Chaos again. This led to Station Square's destruction as a result of the flooding. Having only taken the negative energy, Chaos discarded the remnants of the Chaos Emeralds. This proved to be the means to its downfall as Sonic absorbed the positive energies of the Emeralds and transformed into Super Sonic, eventually defeating it and in the process ridding Chaos of its evil mindset and turning it back to Chaos Zero. Tikal then approached Chaos, and together they disappeared in a flash of light.

Sonic BattleEdit

Chaos Battle

Chaos as it appears in Sonic Battle.

Chaos' latest appearance is in Sonic Battle, where Knuckles the Echidna claims that Chaos appears when there is an upcoming disaster. When Dr. Eggman threatens the Earth with his Death Egg in the final story, a nearby volcanic crater is flooded, and Chaos emerges. It can then be challenged by the player.

Chaos's FormsEdit

Chaos' form and skills change and increase with every Chaos Emerald that it absorbs. Over time it develops from a humanoid water creature to a horrible, world-destroying monster.

Chaos 0Edit

This is the base form of Chaos before it has absorbed any Chaos Emeralds. It is humanoid, and about five feet tall with bright green eyes. Its brain is visible in this form through its watery exterior. Sonic Adventure begins with Sonic fighting Chaos 0 outside the City Hall in Station Square. Its attacks include extending its arms to punch, spinning around with its arms extended and jumping high and quickly onto light posts in order to get out of Sonic's range.

In Sonic Adventure 2, Chaos Zero (as it is called in-game) is a secret character that can be unlocked by getting all 'A's in Rouge's missions. After that, it will be playable as a treasure hunter in 2-Player Mode. In Sonic Adventure 2: Battle, Chaos Zero is an initially available character. It is a very slow character, but has powerful attacks. In this game, Chaos Zero can glide, climb and dig just like Knuckles and Rouge, and it also gains three new attacks: Chaos Impact, a powerful ground punch that creates a small earthquake, Chaos Strike, a blue energy pulse that harms and confuses enemies, and Chaos Bind, a move which freezes the air around the enemy for 30-40 seconds.

After Chaos appears in Sonic Battle, Emerl can challenge it and copy its abilities. After the player defeats Chaos, it is unlocked as a playable character in Battle and Challenge modes. In-game, Chaos is the slowest character in the game but its extendable limbs give it a much wider attack range than it appears to have, and it is very powerful. It can turn into puddle of water as usual, and can create fountains, tentacles, and orbs of water.

Chaos 1

Chaos 1

Chaos 1Edit

After Chaos absorbs one Chaos Emerald, it is virtually unchanged except for a line of bones that travel down its right arm into its hand, where the Emerald is located. As such the arm becomes bulkier. He briefly appears in Sonic Adventure after Sonic or Tails fights Eggman for the first time, and is never fought. Due to never being fought, his abilities are unknown. Knuckles also meets Chaos 1 in the Hotel room just before it transforms into Chaos 2.

Chaos 2Edit

Chaos is much stronger after absorbing two Emeralds. It is taller and more muscular. The bones that were in Chaos 1's right arm now run along both of Chaos 2's arms and now both hands have Emeralds. Its head has moved forward, giving it a more unpleasant appearance, the horns on his head have also changed position to give it a hammerhead style look. It has also developed new powers like a blue energy shield to prevent frontal attacks and the ability to transform into a huge ball, several small orbs, or waves of water. Knuckles the Echidna fights it in the Hotel Restaurant in Station Square. Sonic, Knuckles and Miles "Tails" Prower later meet Chaos 2 by the pool of water in the Mystic Ruins just before it becomes Chaos 4.

In Sonic X, Sonic and Knuckles fight Chaos 2 together right after Sonic defeats Chaos 0. In this version of the fight, Chaos sprays water from his hands and has a near-unbreakable shield of electrical properties.

Chaos 3 and 5Edit

Chaos 3 and 5 were never shown in Sonic Adventure due to the circumstances of absorbing two Emeralds at once in two different instances. This causes it to skip these two forms, but, presumably, he does have these forms.

Chaos 4Edit

Chaos changes considerably after absorbing four Chaos Emeralds. It is now a huge shark-like creature with razor like fins. It fights Sonic, Tails and Knuckles in a small pond in the Mystic Ruins, but is defeated. Its new powers include being able to fire energy waves, swimming at high speeds, creating water explosions, and turning into four balls that bounce toward the player. If Chaos 4 is out of water it simply floats in the air. The third and fourth Emeralds Chaos absorbed are now located in its belly.

Big the Cat encounters Chaos 4 just before it transformed into Chaos 6. Interestingly, even though Chaos' tail is absorbed by Froggy at the time being, Chaos 4 still sports a tail in which he can use for attack.

Chaos 6Edit

After absorbing six Emeralds, Chaos has changed dramatically once again. It is no longer even vaguely humanoid, but a twenty-five foot tall scorpion-like creature. It also has eight or more eyes, a bulldog-like head and a mouth filled with razor sharp teeth. Its tail is tipped with a pendulum type blade. Unlike its previous forms, Chaos 6 cannot be injured by attacking its head, as the brain is too deeply situated to be damaged. (Interestingly, in Sonic X, Sonic and Knuckles work together to defeat Chaos 6, with Knuckles scooping away Chaos' body with Shovel Claw, and Sonic spin dashing straight through the exposed brain.) Instead, Chaos 6 can only be damaged by freezing and shattering its liquid body. Both Sonic and Knuckles fight Chaos 6 on the Egg Carrier and Big the Cat fishes Froggy out from inside Chaos. Chaos's new powers include creating powerful shock waves and trying to inhale enemies to eat them. He can also make dozens of spikes stick out of his body and smash enemies with his huge tail. The Emeralds it absorbed are now all around its body.

Perfect Chaos

Perfect Chaos emerging from a building in Station Square.

Perfect ChaosEdit

After absorbing the negative energies of all seven Chaos Emeralds, Chaos will become a giant snake-like beast with a mouth extending far beyond its eyes, which for the first time have pupils that resemble a reptile's. At the base of its snake-like body seems to be a huge whirlpool and cyclone. It has large tentacles extending from its base. Perfect Chaos's new powers include creating small tornadoes, firing clusters of yellow and pink fireballs, and firing a huge energy beam from its mouth. It has total control over water as Perfect Chaos is able to flood Station Square with ease. It is the final boss in Sonic Adventure, where only Super Sonic has the power to take it down. In its Perfect form, Chaos was quickly able to shoot down Eggman's Egg Carrier 2, which was a fail safe in case Chaos rebelled.

In Sonic X, Perfect Chaos looks more like the Loch Ness monster due to an increased "back" size and several new tentacles. Perfect Chaos also uses a few more powers, like absorbing projectiles like a sponge and then spitting them back at the attacker through its mouth, using its tentacles to attack (he is seen splitting skyscrapers in half with them), and creating crystal spires and an energy shield.

It should be noted that Perfect Chaos' energy beam has an uncanny resemblance to Godzilla's Atomic Ray and that Perfect Chaos himself looks like Godzilla's rival Biollante. Also, the fact that it destroyed a city may have led Sonic Team to giving it resemblances to kaiju.

It is said that Perfect Chaos is Chaos's negative super form. In the Sonic X comic book, in which it absorbed the positive energy of the emeralds to take down Eggman's mecha, Chaos's positive super form simply looked like an over sized version of Chaos 0 with the seven Emeralds in its forehead.

Later in the Sonic X comics, Eggman used the Emeralds and three robots, one with water powers, one with wind powers, and one with solar energy, combined with Chaos 0 to form Perfect Chaos, but with a robotic armor on it's central torso. It once more wreaked havoc on Station Square before being stopped by Super Sonic, who smashed the controller Eggman was using to control Chaos and the armor, but not before it promptly struck Eggman's hovercraft, sending it flying. Restored, Chaos then went back to Angel Island, and presumably merged back with the Master Emerald.

Artificial ChaosEdit

Artificial Chaos are robotic enemies that appear in Sonic Adventure 2 and Shadow the Hedgehog. The latter explains that the renowned scientist professor Gerald Robotnik had built them as experiments, and based them on "a god of an ancient culture", which is, of course, Chaos. After being created, the experiments went out of control and started attacking anyone in sight.

In Shadow the Hedgehog, Shadow himself appears to have a flashback to his time on the ARK, during the time when the Artificial Chaos went out of control. In the flashback stage, the player can choose to find and destroy them all, or simply stay away to make sure the professor is safe. In any case, the experiments were subdued, and it seems they were perfected as they appeared in Sonic Adventure 2, where they protected the Space Colony ARK. In the stage "The ARK" in Shadow the Hedgehog, Black Doom states that "they are ours now", suggesting that the Black Arms somehow took control of the Artificial Chaos.

The Artificial Chaos are generally large pillars or floating orbs of water, with a mechanical head shaped like Chaos 0's towering on top. They exist in two different versions; P-1 and P-100. P-1:s fight by stabbing their enemies with quick, extremely accurate tentacles of water, or by firing lasers from their green eyes. P-100 Artificial Chaos can split their liquid bodies into dozens of small blue drones (known as Cells) that are controlled by the floating robotic head, but are not armed with lasers. These drones constantly edge their way toward the player and explode on contact. If the player attacks them, they do explode (also causing the Cells around them to explode) but they do not hurt the player. After releasing its Cells, the Artificial Chaos head simply floats, defenseless, in midair until it is destroyed. Some Artificial Chaos seem to lack any intelligence or aiming abilities at all, and simply spin around, shooting lasers in random directions.

Associated Theme songsEdit

Chaos has a number of theme songs in the games that are attributed to itself. The genres of the songs vary.

  • "Boss: Chaos 0, 2, 4" plays during the battles against Chaos 0, 2 and 4. It is also used in Super Sonic's story summaries as there is an image of Perfect Chaos in the backdrop.
  • "Boss: Chaos ver.6" plays during the battles against Chaos 6.
  • "Perfect Chaos Revival" plays during the second half of the battle against Perfect Chaos.
  • " Open Your Heart-Crush 40
  • A special song plays when you fight Chaos 0 during the Story Mode of Sonic Battle. It has no name, but is number 18 in the Sound Test.

Other mediaEdit

Sonic the Hedgehog ComicsEdit

The Sonic the Hedgehog comics echoed the Sonic Adventure storyline, with a number of variations. Chaos and Tikal were both imprisoned in a Black Chaos Emerald, which was broken open by Robians under the control of Dr. Robotnik. This continuity also featured the Freedom Fighters, who assisted Sonic and Knuckles in the victory over Perfect Chaos.

Sonic the ComicEdit

In the UK Sonic the Comic comics published by Fleetway, Chaos is depicted as a much more intelligent and evil beast. Rather than being captured within the Master Emerald, Chaos was actually imprisoned by the Echidnas in a mystic container of some sort (showed fairly briefly). Robotnik somehow got a hold of this container, but never unleashed Chaos from his prison. However, his assistant Grimer released him when he saw that Robotnik was depressed after losing to Sonic so many times; Chaos would devastate the planet and Robotnik would, in exchange for being made leader, use his old Chaos Nullifier device to defeat the monster. Unfortunately, Grimer hadn't realized that the Nullifier didn't work and thus Chaos couldn't be stopped...

In the comics, Chaos has a "fear factor" that instills anyone near him with incredible fear when they are around him, to the point where they fall to their knees petrified. Unlike in the game, in the comic Chaos can talk (though in his first attack he seemed little more than a beast) and is actually a transformed Prosecutor of the Drakon Empire, transformed by Chaos Energy back during the ancient war between the Drakons and the Echidnas.

Chaos attacked the Floating Island in order to absorb the Chaos Emeralds, regaining his intelligence as he came into contact with them; Knuckles was forced to jettison the Emeralds, this sacrificing the Island, and the Freedom Fighters tried to locate them before Chaos could. Unfortunately, Robotnik - attempting to bring about Mobius's destruction - deliberately set things up so they couldn't trace the Emeralds and Chaos would get them all first. The creature transformed into Perfect Chaos (which resembled Chaos 6 from the game). Eventually Super Sonic (who at this point in the comic was separate from normal Sonic) absorbed all of Chaos's energy and Chaos reverts back to his fish state.

In the Fleetway adaptation, Chaos's most infamous act was murdering one of Sonic the Comic's longest running characters, Johnny Lightfoot.

Sonic XEdit

The Sonic X anime follows the plot line of Sonic Adventure in episodes 27-32, resulting in Chaos's presence in those episodes in several of his many forms. However, Chaos's origins differ in the fact that it is described as "liquid Chaos energy" rather than the "God of Destruction".


  • In Sonic Adventure 2, it is shown that Chaos has two fictional soft drinks named after itself; Chaos Cola and Chaos Soda. Billboards advertising the drinks appear in several stages, such as Shadow's "Radical Highway" stage.
  • Also in Sonic Adventure 2, Chaos 0 can be seen on billboards advertising a fictional movie named "Planet of the Chaos", apparently based on Planet of the Apes. This billboard can be seen in Sonic's "City Escape" stage and "Big Foot" boss battle. The movie is shown to be rated PG-13 by the MPAA.
  • There is a special kind of Chao called a "Chaos Chao", whose head resembles that of Chaos 0.
  • Chaos appears on four collectible cards in Sonic Rivals, in its 0, 2, 4, and 6 forms.
  • Perfect Chaos bears a striking resemblence to the Kaiju monster Biollante.