The Biolizard (also known as "The Prototype of The Ultimate Life Form") is a giant bio-mechanical creature and the final boss of Sonic Adventure 2. It appears as a giant lizard with a life support system on its back with tubes running down its neck to its head. The Biolizard is 85 meters (280 feet) long, 30 meters (100 feet) wide, 19.5 meters (64 feet) tall, and weighs 87.5 tons. After the final version of the Ultimate Life Form was created, the Biolizard was to be encapsulated but never was.