The Chao Life-Cycle
Chao go through several stages in their lives, starting as an Egg, evolving via a cocoon, and then if it has had a good life; entering another cocoon and emerging as an Egg once more! The cocoons in the Dreamcast games are always white, but in the modern games (except SADX Steam due to a bug) the colour of the cocoon will be different depending on the stage of the Chao’s life-cycle. Look at the illustrations below to see the difference between the games.
All Chao begin their lives in eggs. This stage usually lasts just a few minutes, and ends when the Chao hatches.
After hatching from their eggs, Chao are considered to be children. This stage usually lasts one Chao year. Throughout this stage the Chao undergoes a gradual transformation, where its shape and colour changes depending on its interaction with characters, fruit, animals, and Chaos Drives. This stage ends with a metamorphosis in a cocoon; this is called the first evolution. The cocoon is always white for dreamcast and blue-green for the modern versions.
The Chao is an adult after emerging from its first evolution cocoon. This stage is the longest part of your Chao’s life, usually lasting four Chao years. Similar to the child stage, an adult Chao undergoes a gradual transformation, where its shape and colour changes depending on its interaction with animals and Chaos Drives. This stage ends with a second cocoon as the Chao dies.
Depending on how happy the Chao had become by the point of its death, it will either reincarnate as an Egg once more, or it will die and be gone forever. In the modern games, it will either enter a white cocoon or a pink cocoon. A pink cocoon indicates that the Chao has enjoyed life and is reincarnating. After a Chao reincarnates, an egg will be left so that it can enjoy life another time. A white cocoon indicates that the Chao is dying forever; no egg will be left, and it will be the end of its life cycle. On the Dreamcast versions (and SADX Steam due to a bug), cocoons are always white - so you won’t know if the Chao has reincarnated or not until the cocoon fades away leaving either an Egg or an empty space!
What came first, the Chao or the Egg? Well in the Sonic Adventure games you always start off with a Chao Egg in the gardens!