Art by Roberto Corona
A robot gorilla was a Badnik that was left on Flickies' Island as an automatic defense against intruders should Doctor Robotnik no longer rule over the landmass. Resembling a normal gorilla from Planet Earth other than a purple, metal exterior, the Badnik attacked using sheer strength to punch its foes or pounded the ground to cause shockwaves. The threat came across tourists tricked into visiting the island by Max Gamble but was quickly disposed of by Sonic the Hedgehog. Despite its size, the beast still only carried a solitary pink Flicky as an organic battery.
In the Kid Chameleon series, a sort of "cyborg gorilla" acted as the final boss of Wildside the first time Casey was stuck there. As Iron Knight, the hero ordered Suzi to flee and leapt straight into battle, but his sword was immediately destroyed by the gorilla. Casey was then forced to fight the beast as a normal schoolkid, deprived of his chameleon powers. Like the Flickies' Island type, this gorilla would use its strength to punch the floor to cause minor tremors, but its real strength was in firepower positioned all over its body. With shoulder-mounted lasers and an eye cannon, the gorilla should have won, but Casey used his own abilities to throw his skateboard into the mouth of the enemy before kicking him off the skyscraper. The monkey was presumably killed.
Others
Although not gorillas, robot monkeys can be observed in the Coconuts and Monkey Dude Badnik designs. Kiki also seems to appear in Sonic the Comic Online.