Throughout played by Jim Carrey in dual roles, who recruits both Ivo and Shadow in his plans for world destruction.

Shadow the Hedgehog's origins and Jim Carrey's dramatic and outlandish performances of both Ivo and Gerald Robotnik. Throughout Sonic 3, grandfather and grandson Robotnik are shown to be very similar in many ways, including their unusual fondness for licking the quills of both Sonic and Shadow the Hedgehog. However, it's revealed each Robotnik does so, for different reasons.

Ivo Robotnik Licks Sonic's Quills To Get A Taste Of His Power

Doctor Robotnik Uses Sonic's Quill To Power His Numerous Inventions

In Sonic 3, after Shadow easily overpowers them in Tokyo, Sonic, Tails, and Knuckles reluctantly seek help from Ivo Robotnik. After Robotnik's disappearance in Sonic 2, he falls into a depressed and obese state, with no interest in his previous schemes. However, upon learning of the impostor using his weapons, Robotnik agrees to align with Team Sonic on one condition: that Sonic allows him to lick one of his quills. Despite Sonic stating "Robotnik needs help," he complies and the taste of Sonic's power in his quill motivates Robotnik to straighten himself up and tidy his appearance.

As a running gag, throughout the Sonic the Hedgehog franchise, Ivo Robotnik licks Sonic's quill, and gets himself electrocuted; this first happens during Sonic the Hedgehog, after Robotnik and Agent Stone take the quill for examination in their laboratory. Robotnik's electrifying taste of Sonic's quill gives him an idea of how powerful the hedgehog really is. Sonic's quill eventually becomes Robotnik's secret weapon in the Sonic franchise, as he uses its energy to power up his weapons, including the Egg-Pod. Robotnik's use of Sonic's quill also eventually helps him escape the Mushroom Planet at the start of Sonic 2.

Gerald Robotnik Licking Shadow's Quills Helped Him Live Longer

Gerald Robotnik Is 110 Years Old In Sonic 3

Sonic the Hedgehog 3 introduces Gerald Robotnik, Ivo's grandfather. Throughout the threequel, it's shown that the elder Robotnik also shares his grandson's fondness for tasting quills and getting electrocuted, as he is regularly shown licking one of Shadow the Hedgehog's quills that he has held onto for 50 years, after the tragic death of Maria, his granddaughter. Gerald Robotnik's surprise appearance in Sonic 3 is a change from the movie's basis, the Sonic Adventure 2 video game, where he's revealed to be long deceased. Director, Jeff Fowler, revealed in an interview that Gerald Robotnik's longevity was assisted by Shadow's quill.

Sonic 3's ending, the Robotniks' fondness for quills proved beneficial for saving humanity, as Ivo ends up using Sonic's quill to stop Gerald from destroying Earth in Sonic the Hedgehog 3.

Source: ComicBook