Dr Eggman

Dr. Eggman is an evil and megalomaniacal genius who is constantly planning to take over the world and those beyond his. Showing contempt for how "filthy" and "irregular" the world is, he views himself as obligated to perfect it by ridding it of what he deems as imperfections, including hunger, disease and, above all, free will. Arrogant, raucous and explosive, he believes that he is bringing peace and unity to the world under his brilliant leadership. He also does not accept the world as it is as a whole. Instead, he wants to transform it to his liking and set up terrifying amusement parks like Eggman Land. His reasons for doing so is that he simply likes amusement parks and does not care about their effectiveness; all he wants is to control precisely what his enemies experience in their last moments. Eggman likewise prefers to show up and claim responsibility whenever he is carrying out his villainous deeds and make himself known to his enemies after he comes back from a defeat; as put by Sonic, subtlety is not Eggman's forte. 

Mr Tinker

Mr. Tinker retains his personality from the IDW Sonic the Hedgehog comics. Unlike the insane, evil, megalomaniacal Dr. Eggman, Mr. Tinker is kind, friendly, and eager to help. He is noted to be the complete opposite of Eggman, as he was friendly and polite to everyone he met, but he cowered from fights.