The development that went into him, and all of that, was made so great, just by the casting of Jim Carrey, and all the ideas that he brought to it.
It just felt like he really responded to the character in the most incredible way, and had so many ideas for how to develop him.
I mean, we still obviously had a lot of fun with the character.
With Robotnik, there wasn’t quite so much to pull from with the source material, because he is very moustache-twirly, and for the purposes of the film, we were trying to keep him a little bit more grounded.
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Sonic The Hedgehog (2020) - Becoming Robotnik - Paramount Pictures