As Mr. Tinker, Eggman displayed a very different disposition, being a friendly, humble and modest man who loved children and helping others out. Mr. Tinker also displayed a somewhat cowardly streak, being afraid of his own robots, although it did not keep him from helping and comforting the innocent.

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 free will. Arrogant, raucous and narcissistic, he 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.