E-10000G (called Robo 2 on the official American website of Sonic Riders) is a robot created by Doctor Eggman. It is very similar to E-10000R, except it is green and seems to be mass-produced.
E-10000G is a Power Type character in the game. However, when met as opponents in the World Grand Prix in Story Mode, he has the abilities of speed, flight and power characters. In Story Mode, he fills in spots not used by other characters. He is equipped with a large light in its body that it can use to blind opponents, and also punches enemies with its fists. E-10000G's unique Extreme Gear is called the E-gearG and it is unlocked as a playable character by playing for twenty hours. In a normal race, E-10000G can only use Board type Extreme Gear.
E-10000G also appears in Sonic Free Riders as a playable character. His role in the World Grand Prix (Story) mode mirrors with that in Sonic Riders. In a normal race, E-10000G can only use Board type Extreme Gear. However, on the E3 demo, he is credited simply as E-10000.