G-merl

G-merl (also known as Gemerl), is one of the main antagonists turned-anti-hero in Sonic Advance 3. He is a Gizoid created by Dr. Eggman from Emerl's data, making him a revised version of his predecessor. G-merl once aided the doctor in his attempts to stop Sonic and his friends from foiling one of his plans, but wound up betraying Eggman to cause mayhem. After his defeat, he was reprogrammed in the image of his predecessor.

Ultimate G-merl
As G-merl and Dr. Eggman escaped from their defeat at Altar Emerald, G-merl began short-circuiting. Then, without warning, presumably due to his battle damage and Emerl's data, G-merl struck Sonic, forcing the blue hedgehog to drop the seven Chaos Emeralds. G-merl then harnessed the seven Chaos Emeralds to transform into Ultimate G-merl. After his transformation, Ultimate G-merl first act was to betray Dr. Eggman, by grapping the doctor in his Egg Mobile and throwing him at Sonic. Ultimate G-merl then took off into space to cause more havoc elsewhere, but not before discarding the Chaos Emeralds.

After having made it into space, Ultimate G-merl was pursued and challenged to a battle by Super Sonic and Dr. Eggman, the two adversaries having put aside their personal vendettas to stop the rogue robot. Ultimate G-merl fought the unlikely duo, but defeated and reverted back to normal in a large explosion, before falling back down to Earth.