Supplies:sonic adventure 2 battle, sonic advance, controller link cable.
Step1:Get at least 500 rings in sonic advance and buy a silver metalic egg.
Step2:Transport the egg to sonic adventure 2 battle.
Step3:Hatch and transform the chao to make it adult.
Step4:Somehow obtain a shiny chao. (buy or breed).
Step5:Mature that chao to adult and then buy 2 heart fruits. Feed the chao the fruits and then breed them. If u got a shiny grey or shiny white then you will have a chao that has only the eyes, ball, mouth, and wings. If you got a different shiny color, it doesn't matter, because it will look awesome anyway. For example, a bred my silver chao with a shiny orange chao and (wierd as this is) out from the egg a shiny transparent lime-green chao hatched