Biolizard
From Sonic Earth
Biolizard, the Prototype of Ultimate Life, is a creature which appears in Sonic Adventure 2 as the second to last boss, and final boss, and in episode 38 of Sonic X under the same role. It is also seen briefly in a flashback in Shadow the Hedgehog. The Biolizard appears as a giant and alien looking lizard with a life support system on its back with tubes running down its neck to its head. According to Sonic X, the Biolizard is 85 meters long, 30 meters wide, 19.5 meters tall, and weighs 87.5 tons. The massive creature can either attack by trying to bite its enemies with crushing jaws, or attempting to hit them with its tail. Biolizard can also spit large black orbs from its mouth and create smaller, but extremely numerous, pink egg-like orbs that it can shoot at a target. Additionally, as a product of Project Shadow, the creature can use Chaos Control.
The Biolizard was an earlier version of "Project Shadow", a government project run by Professor Gerald Robotnik that was intended to create an "Ultimate Lifeform" as a first step towards humanity discovering the secret of immortality. Due to the experiments, it later needed a life support system. While the Biolizard was successful in the way that it was could regenerate and restore itself, and could self-reproduce, it was also unruly and dangerous. It was closed down when Gerald, with the aid of the alien Black Doom, produced a more advanced being: Shadow the Hedgehog. When GUN came to Space Colony ARK in order to put a stop to Professor Gerald's plans, they found the Biolizard and shut it down. It didn't go without a fight, however, and it killed almost all of the GUN soldiers.
The Biolizard remained encapsulated aboard the ARK until Doctor Eggman placed the seven Chaos Emeralds into the Eclipse Cannon. This initiated a hidden program by Gerald, that would use the Emeralds to power the ARK into a doomsday causing collision with the planet below. The program released the Biolizard to defend the Armageddon plan from tampering by the combined forces of Eggman, Sonic the Hedgehog and friends. But Amy Rose had convinced Shadow to help save the Earth, and he engaged and defeated the giant reptile in battle by damaging its Life Support System. Not giving up, the Biolizard then used Chaos Control to teleport outside and fuse with the space station itself, becoming the Finalhazard, to drag the ARK into its collision on its own. As Finalhazard it attacks with the pink orbs and firing out energy beams from its damaged Life Support System. It was, however, weakened by the loss of its Life Support System and was destroyed by the combined power of Sonic and Shadow in super form, who then used Chaos Control to place the ARK back into orbit.
