The final boss of Sonic Adventure 2. It appears as a large, red lizard with multiple mechanical contraptions across its body. It was created at the ARK by Professor Gerald Robotnik as a prototype of the Ultimate Life Form during Project Shadow. It was capable of multiple physical feats, such as using Chaos Control, but needed a life support system to sustain itself.
50 years after its creation, it would try to take the ARK into a collision course towards the Earth, but it was stopped by its eventual successor, Shadow, along with Sonic.