A Chao is an artificially intelligent, virtually generated lifeform from the Sonic the Hedgehog series. Their role in the games is to be raised by the player in mini-games, similar to Tamagotchi. Chao are somewhat complex, responding to stimuli; they have moods, they require food, and they can be loving or fearful. The word Chao is a pun on Chaos, a word commonly used in the Sonic series.
Making their first appearance in Sonic Adventure for the Sega Dreamcast (both in the plot and in a Chao-raising aspect of the game), later in Sonic Adventure 2, and further enhanced in Sonic Adventure 2: Battle and Sonic Advance, Chao have recently come to be a large part of the Sonic the Hedgehog franchise. The A-life system used for the Chao was introduced in Nights into Dreams... as the Artificial Intelligence in the Nightopians. Chao-raising and the main Sonic games tie together in a number of ways: items which you encounter in the main game can be used to raise your Chao, collected Rings can be used to buy things for them, and several unlockable features are related to Chao. Many different kinds of chao can be made, including a transparent chao (mating a shiny purple fly type devil with a silver jewel [only obtainable on gameboy game of sonic advance] power type chao. The silver one coming to the purple one, resulting in a regular looking chao that you can see through), an invisible chao (mating a shiny yellow chao with a pink jewel chao, resulting in an invisible chao [you can only see it's eyes, emotion ball, and wings]), and even a two toned shiny green chao (parents were a shiny two toned yellow and green shiny chao and a silver jewel chao). other sites have more rare chao recipes. During raising, Chao have statistics: Swimming, Flying, Running, Power, and Stamina, as well as luck and intelligence, which aren't quite as obvious. These statistics can be raised through proper Chao raising, and will enable a Chao to do better in their competitions: racing and karate.
Chao start life in an egg state. There are several different eggs, reflecting the type of Chao that will hatch from them. Speckled eggs, found in the Gardens when no other Chao are present, hatch neutral chao; these Chao are blue with yellow highlights by default, but may change color as they grow. Colored, shiny and jewel Chao are purchased and maintain a single color throughout their lives; additionally, shiny Chao sparkle and jewel chao have a metallic sheen.
Ways of hatching them include snuggling the egg (which will cause the Chao to initially like the character) or throwing the egg against a wall (which will cause the Chao to initially hate the character) or even simply waiting for the egg to hatch on its own. Once hatched, the eggshells can be sold for a fourth of their value when purchased, excluding speckled eggshells, sold for 50 rings. The eggshells can also be used as hats.
When Chao hatch, they may be trained and have different attributes and personalities. Chao from Sonic Adventure DX, Sonic Adventure 2, and Sonic Adventure 2 Battle can also favour "dark" and "hero" sides as well as the default "neutral" side which can lead to variations in visual evolution. Depending on the game and environments, they take varying times to evolve.
After awhile,or when stamina is level 16, a Chao creates a cocoon and evolves into a more mature form. When evolving, they go into a cocoon state, which is white in the SA2 Dreamcast version of the game and blue for the GameCube version. When the Chao comes out of this cocoon, it is an adult and can mate.Giving a chao an item to hold while evolving will give a chao a hat. The Chao ages by one year around every three to four hours, depending on a number of environmental influences. In no fewer than eight hours, the Chao will enter another cocoon; if the Chao was treated lovingly, it will be surrounded by a pink cocoon, and it will come back to life again as an egg, and all its stats will be one tenth of their original value. However, if it was treated cruelly, or not looked after at all, it will be surrounded by a gray cocoon, and it will die.
The Chaos Chao Through regular care, a Chao will follow the same pattern of Birth then Evolution then Reincarnation, as long as the Chao is treated well by the player. But there is a way to have a Chao evolve so it become immortal: The Chaos Chao. The Chaos Chao is named after the Sonic Adventure character Chaos who was the original guardian of the Master and Chaos Emeralds and Chao. In Sonic Adventure there was only one form of Chaos Chao, the Light Chaos Chao or just Chaos Chao. Its body appears icy-white with pupil-less green eyes. The tips of its "hair" are a transparent ice-blue. Its feet which are white fade into a ice blue. Its hands are small "ice" claws. Its emotion-ball also becomes a ball of light. Its general appearance is very similar to a 'chibi' 'Chaos'. With the inclusion of alignment based evolution forms in 'Sonic Adventure 2', two more Chaos Chao forms were added for Hero and Dark, with Light Chaos Chao being the neutral form. The Hero evolution form also known as Angel Chao, is very similar in appearance to the Light Chaos Chao, except for few parts. It appears to have grown large wing-like "ears" that end in a transparent crystal pink. Its hands appear as crystal pink mittens with a thumb, its feet are white ending in a speckled pink. Lastly the emotion ball changes into a a pink transparent 'halo'. The Dark evolution also called a Devil or Demon Chao due to its appearance is very different in appearance to the other two Chaos forms. First off it is colored black. It has a pair of medium-sized black with red tipped horns on top going up and a pair of large crystal orange-red horns that face downward. It has clawed crystal orange-red with small spikes or thorns around its wrists. Its feet are a fade from dark purple to a lighter shade. Its emotion ball changes into a small blue flame (a similar effect can be obtained by giving a Chao the Half-fish). All Chaos Chao all share a lack of wings and tails (with the exception of the devil chaos chao which has a tail with an arrow tip). These colors only apply to Normal egg Chao or the Standard blue with yellow Chao, different colored Chao look the same only they retain their special colors, this can be used to create interesting and unique looking Chaos Chao. When a Chao becomes a Chaos Chao, they lose the ability to mate and giving them animals will no longer give them special parts (but they still gain stats), but they can still wear Hats if the player wants them too. To obtain a Chaos Chao you must follow these steps.
- 1. Choose the Chao you want to become a Chaos Chao.
- 2. Raise the Chao so its goes through at least two life cycles.
- 3. On its third ( or later depending if you mess up or not) life cycle, give the Chao one of every animal once no more, no less and no Chaos Drives.
- 4. Depending on the game your playing will determine this step.
- 4a. If you're playing Sonic Adventure for the Sega Dreamcast you have no choice but to the get Light Chaos Chao.
- 4b. If you're playing Sonic Adventure DX: Director's Cut for the Gamecube you can choose the form depending on which alignment fruit you feed the Chao, Hero to get Angel; Dark to get Devil; or nothing to get the Light Chaos Chao.
- 4c. If you're playing either Sonic Adventure 2 for the Sega Dreamcast or Sonic Adventure 2 Battle for the Gamecube. If you want the Angel Chaos Chao, take care of the Chao with a Hero character; if you want the Light Chaos Chao take care of the Chao with both Hero and Dark Characters evenly; to get the Devil Chao take care of the Chao with only Dark characters.
- 5. Have patience and wait for the Chao to evolve.
Alignment is determined by how the Chao was treated before its evolution. The three alignments are Dark, Hero, and Neutral. There are three Hero characters (Sonic, Knuckles, and Tails) and three Dark characters (Shadow, Rouge, and Dr. Eggman) in Sonic Adventure 2. Petting, holding, or cuddling a Chao with a character makes the Chao favor the character's alignment. Attacking, throwing, or stepping on a Chao makes it favor the opposite alignment of the character.< Every time that a heart appears above a Chao's head and replaces the standard emotion, the Chao darkens or lightens a shade, a darker shade coinciding with becoming a Dark Chao, and vice versa. A Chao's physical appearance is the chief indicator in understanding the alignment of a Chao. It will become whichever type has influenced it the most by the end of its child lifespan. It is not based on stats. Dark Chao have bat wings, a spike ball above its head, a bent tip on its head and a devil's tail, and are colored black, brown, and red. Hero Chao have feathery wings, a split tail, an Angel's halo, and a cowlick type object on its head. They are colored white, blue, and gold. Neutral Chao are created by balancing contact by both Hero and Dark characters. They are able to look like a lot of different characters. In Sonic Adventure DX, due to only heroic characters being playable, the Chao instead become Hero or Dark depending on the fruits it is given. Hacking can also give the player character Chao, such as Amy, Knuckles, and Tails Chao (although Tails Chao can be legitimately obtained from Phantasy Star Online Episode I & II).
After evolving, Chao gain the ability to reproduce. Chao are genderless, and therefore can breed with any other adult Chao. Chao are in mating season when surrounded by a circle of flowers. While this happens twice naturally, it can also be achieved by purchasing 'Heart Fruit' from the Black Market in Sonic Adventure 2 Battle games and by finding them while playing the Chao Adventure 2 V.M.U. mini-game. Giving them to an adult Chao will make the chao go into a mating season. 'Heart Fruit'-induced mating seasons will not affect a Chao's lifespan. Depending on two Chao's opinions of one-another, they may mate naturally when one realizes the other is in mating season.
By giving a Chao a "small animal", it will acquire some of the animal's characteristics. Besides a physical change to the Chao, this will also modify the Chao's stats based on the type of animal given. There are five types of animals in Sonic Adventure and 7 in Sonic Adventure 2. They consist of Running (Green), Power (Red), Swimming (Yellow) and Flying (Purple). The fifth color, Blue, is an even mixture of some or all of the other classes. The two additional types featured in Sonic Adventure 2 are Ghost (Black) and Imaginary (Orange), sometimes called Legendary. The Imaginary Animals consist of the Phoenix, Dragon, and Unicorn while the Ghosts consist of a Bat, Skeleton Dog, and Sea Creature (also known as a Kappa and Half-Fish). Giving a Chao a Skeleton Dog allows it to wear hats that are given to them by the playable characters. When this happens, the Chao will be able to wear any kind of hat for it's life span, but this is not required. The Ghost and Imaginary animals give better than average stat increases and do not lower any stats. Some special Chao look the same, but do special tricks. For example, giving a Dragon to a Chao will give it the ability to breathe fire. Also, through evolution, it is possible to make a Chao that look like Sonic, Shadow, or even NiGHTS. To make it look like Shadow or Sonic, give it run things only and raise it with Dark characters(Shadow) or both Hero and Dark characters (Sonic).
In Sonic Adventure 2, Chaos Drives appear and, like the small animals, also raise a Chao's stats. Chaos Drives are items that come out of machines created by the police organization G.U.N. when they are destroyed. However, neither animals nor Chaos Drives can raise a Chao's stamina, only food can. Also, a certain fruit called the Chao Fruit raises all stats, including Stamina, when it is given to a Chao. These are only in Sonic Adventure 2 and the GameCube adaptations Sonic Adventure: DX and Sonic Adventure 2: Battle. Like the small animals, the different colors each raise a certain stat. Yellow raises swim, purple raises fly, green raises speed, and red raises power. There is a rumor that there is a blue Chaos Drive, but these do not exist. Chaos Drives only raise the stat the color represents. A Chao's statistics control what type of Light/Dark/Neutral Chao it will become. For example, a Dark Power Chao looks different from a Dark Running Chao. Also, a Chao can have two different skill types if it is in its second life. For example, a Dark Power/Power Chao looks different from a Dark Power/Run Chao. Also, a Dark Power/Run looks different from a Dark Run/Power.
The Chao's "emotion-ball" on top of its head will tell you at a glance the Chao's mood:
Normal: The Chao is not feeling anything in particular. Neutral Chao have a standard emotion-ball, but Hero Chao have a halo and Dark Chao have a spiked ball. Giving Chao an animal called a Half-Fish will turn the emotion-ball into a small flame.
Heart: The Chao is feeling very happy. This occurs when fed, pet, cuddled, or loved. If a Chao is sitting on the ground with a heart along with a circle of flowers, the Chao is ready for mating. Question Mark: The Chao is thinking or is confused. Exclamation Mark: The Chao is excited or surprised by something. The Chao will show this emotion after being whistled by a character it likes upon making eye contact with, or if the Chao discovers something it wants to do, like play with the beach ball or other Chao toy. If the Chao is very hungry and finds food on the ground, it will run to it with this mark on its head. Swirly Mark: The Chao is very upset or hurt. This occurs when a Chao is awakened while sleeping, hurt by a character, when it falls over trying to run towards the character or when the chao is thrown. When you walk into the chao garden and your chao is sitting with a swirly mark above its head that means it's dying.
Conversely, Chao abuse is a somewhat obscure form of Chao raising, in which one abuses their Chao. This can be done in a manner of ways, such as starving a Chao, leaving it in the water when it can't swim, or simply inflict physical harm upon it. Awaking the Chao while sleeping will upset the Chao more than anything. Chao abuse usually decreases the lifespan of the Chao, and the Chao dies when it comes time to reincarnate. One reason for Chao abuse is to "help" a Chao change alignment by abusing it with a character of the opposite side. However, mistreatment is in no way necessary in order to change a Chao's alignment, as treating them kindly with a character of the desired alignment (or feeding them their least favorite fruit with the undesired alignment) works just as well.
If a Chao is treated poorly by the character, it will usually stand and shiver in fear if the abusing character is close by. When the Chao is held it will try to squirm out of the character's hands for fear of being hurt. If the Chao has been particularly abused, it might run away screaming and crying from the abuser, or even run up to them and attack them (this has no effect on the character). On the other hand, if a Chao is treated well by the character, it will run happily towards the character after whistling, will nuzzle against the character when it wants attention, and when held or snuggled by the character, will smile and clap its hands. Also, Hero/Neutral Chao will sometimes bow to the character, while Dark Chao will grin and give the character a thumbs-up instead.
In Sonic Adventure and Sonic Adventure DX: Station Square is the first garden you can go to in the game. It's inside a hotel, it has a pool for the Chao to swim in. Mystic Ruins is the second garden. It is found by going near Tails's workshop in the cave, then you ride the cart. It has a big pool, an island in the middle of the pool, and a few rocks. The last garden in the game is found in the Egg Carrier. You have to put in the password "EGGMAN". It is like a beach. has one chair in it and a large missile where Chao can jump off and fly.
In Sonic Adventure 2 and Sonic Adventure 2: Battle, The normal garden is the first garden with a pool, and a cave near the pool where you can do the Chao Race and Chao Karate. Raise a Hero Chao, and an upwards staircase will appear in the lobby. This garden has a large pool, fallen down marble pillars, and a gazebo-like structure with a ledge where Chao can get up and fly. Raise a Dark Chao, and a downwards staircase will appear in the lobby, this one leads to the Dark Garden. It is decorated with tombstones, a large dead tree with a cage hanging from one of the branches, and a pool of blood.
There are "Chao Gardens" in Sonic Adventure and Sonic Adventure 2 to raise the Chao. In Sonic Adventure 2 and Sonic Adventure 2 Battle two more gardens are unlocked, there will be stairs from the main Chao Lobby. The one upwards leads to the Hero Garden and the downwards leading to the Dark Garden.
The gardens in Sonic Adventure and Sonic Adventure 2 Battle have the ability to send Chao to an attached VMU (, and play with the Chao away from the Dreamcast in a game called "Chao Adventure". The Chao walks on a path and is given a task. If done correctly, you are rewarded with a fruit or seed which can be taken off the VMU and back onto Sonic Adventure 2 for planting. Seeds can be planted by a Chao with a shovel and a watering can. The shovel can be won in races in Sonic Adventure 2. On Chao Adventure, you can also attach two VMUs to mate Chao, check the stats of your Chao, and name it. In Chao Adventure, the Chao doesn't age like it does in gardens.
Every Sonic Advance, Sonic Advance 2 and Sonic Pinball Party also has a "Tiny Chao Garden" of its own, which is a small simple garden with a small pool that is universal to every game. There is a shop where fruit and toys can be bought for the Rings that the player has collected during gameplay, and some minigames. The Chao can be transferable between these games and Sonic Adventure DX and Sonic Adventure 2: Battle via a GameCube/Game Boy Advance link cable.
Sonic Advance 3 has a Chao Garden, but it is not for raising Chao. Instead, it is an area where the hidden Chao that the player has found during gameplay are located. When all ten of the Chao in the zone are found, the player can look for keys that enable the Special Stage for that particular zone.
In Sega Superstars, an Eyetoy game for the PlayStation 2, there is a simplified Chao Garden, where you can pet and tickle a single Chao by waving your hand on its head, or its belly. It includes many elements from the other games, such as feeding, toys and pool, though it omits any breeding aspects.
Chao appear in Sonic Rivals 2. Several of them are kidnapped by Eggman Nega to feed to an inter-dimensional beast called "Ifrit". Silver and Espio hid most of them, while Sonic the Hedgehog and Tails set out to rescue the rest (with success).
- Sonic Adventure — A poster found outside Casinopolis advertises a film called "Chao in Space". This may be a reference to Lost in Space, and the poster resembles the posters for the movie Muppets from Space.
- Sonic Shuffle — A neutral Chao is a playable secret character.
- Sonic Adventure 2 — Posters in the City Escape stage advertise "Chao in Space 2", featuring a Hero and a Dark Chao. The poster also mentions that it is "now on DVD". A billboard with a Chao on it can be seen beside the road in the Kart Racing stages and mini-game. The billboard reads "Drive Safety!" instead of the correct "Drive Safely!"
- Phantasy Star Online Episode I & II — Through a secret mission it is possible to receive a "Tails Chao". This Chao resembles Tails to a great extent and can't die or reproduce, much like a Chaos Chao.
- Sonic Adventure 2: Battle — In the first boss battle of the Hero story, a poster advertises a film called "Planet of the Chao", a reference to Planet of the Apes.
- Sonic Heroes — Chao appear in some Special Stages, where a Neutral Chao and a Dark Chao float in front of the characters in a hot air balloon. The Neutral one throws power orbs to help the characters, while the Dark one throws mines. Team Chaotix are given several missions that consist of finding and rescuing Chao. A special "chocolate" Chao named Chocola is one of the three main focus points for Team Rose. When Cream the Rabbit is the only one able to attack, her Chao, Cheese is sent out to attack for her.
- Shadow the Hedgehog — Dozens of Chao can be found frolicking in Doctor Eggman's Cryptic Castle base. They can be attacked, which makes them cry and slightly raises Shadow's "dark" meter.
- Sonic Riders — A Chao hot air balloon similar to the ones from Sonic Heroes can be seen flying overhead during a race. It is from this lofty perch that the robotic Chao Omochao delivers its commentary on the race.
- Phantasy Star Universe — There are rare monsters called "Jaggo" which looks like a more vicious version of a Chao. Also, there is a Room Decoration item called a "Jao", that resembles a normal Chao. The Phantasy Star Online series was also created by Sonic Team.
- F-Zero GX — If a player were to fall off the course during a multiplayer game, the recovery spaceship that brings the player back on course is piloted by three blue raindrop like aliens that resemble Chao.
- Billy Hatcher and the Giant Egg — A Chao appears as an Egg Animal for the first mission in the game.
- Sonic the Hedgehog (Xbox 360/PS3) — A billboard can be seen occasionally in the "Crisis City" stage. This billboard advertises "Chao in Space 3", another sequel to the previous movies. A sign saying "Chao Garden" can also be seen.
- Mario & Sonic at the Olympic Games - Several different Chao appear in many forms throughout the game, including Chao in the audience and a Chao hot air balloon. Chao also appears alongside Toad in the indication that it's time to take a break.
- Sonic Riders: Zero Gravity - A Chao appears as the salesman at the shop where the player buys board upgrades and equipment.
- Sega Superstars Tennis - The Green Hill tennis court features many Chao as well as Blaze, Knuckles and Big.