"Grounder the Genius" is the twenty-third episode of Adventures of Sonic the Hedgehog television series. Despite being produced as the twenty-third episode, it originally aired as the tenth episode during the show's original run.
In his fortress, Dr. Robotnik is downloading a genius program that is supposed to improve his intelligence. Meanwhile, Scratch and Grounder are setting a trap for Sonic the Hedgehog, which fails as usual. Eventually, they head back, where Robotnik is still searching for more brain power, attempting to download other computer programs. However, this results in a computer virus infecting his computer, which Sonic and Tails' friend Hacker created when copying the genius program onto a microchip. Hacker is almost captured but is saved by Sonic.
Later, Grounder's head loses various bits and pieces. During his search for the pieces, he accidentally grabs the Genius Chip, and when he places it in his head, he becomes a genius. Sonic tries to get the chip back, but ends up getting zapped by a ray that Grounder reveals has turned him to stone. Grounder then starts treating Robotnik like a prisoner, and Scratch like a slave.
Eventually, Hacker and Tails manage to reverse the ray that zapped Sonic. They discover that he was not turned to stone, but rather encased in stone and Sonic breaks free. Scratch tries to help Grounder take care of Sonic, but Grounder's head falls off, allowing Robotnik to remove the chip while Sonic switches the chip with another. This in turn makes Robotnik stupid. Robotnik then takes it off and yells "I HATE THAT HEDGEHOG!".
Sonic was turned to stone (or rather trapped in stone) in this episode, whereas a similar event occurred again in the episode "Tails in Charge". However, in that episode, it served as a larger part of the story.
When Robotnik goes to press Grounder's "off" button, he clearly presses the "on" button and still gets electrocuted, despite the fact that Grounder had disconnected the "off" button.
When Grounder turns his head to look at Robotnik, Robotnik is still electrocuted, despite the fact that he isn't touching the "off" button.
After the attack on Hacker's lab, Hacker gives Sonic the Stupid Chip, which is noticeably yellow. However, when Robotnik applies it after Sonic performs the switch, it is red.
When Sonic shows Scratch the Stupid Chip, his arm looks like Tails' arm.