The Kintobor Family is an old Overlander clan dating back to before the Xorda Attack on Earth. The earliest known member of this family was Ivan Kintobor, who created the robot known as Isaac before placing himself in cryogenic stasis, later perishing. However, his family line evidently survived, the next known representative being one Brutus Kintobor, who led an Overlander party to Angel Island during the time of the Guardian Steppenwolf. The Kintobor family was later united with the family of Gerald Robotnik through the marriage of Ivo Kintobor to his daughter Bertha, with this union producing the most infamous member of either clan: Dr. Julian Kintobor, also known as Ivo Robotnik and Dr. Eggman.
- Ivan Kintobor (earliest known member)
- Brutus Kintobor
- Ivo Kintobor (Gerald Robotnik's son-in-law)
- Bertha Kintobor (Gerald's daughter, Ivo's wife)
- Colin Kintobor (Ivo's oldest son)
- Julian Kintobor/Dr. Ivo "Eggman" Robotnik (Ivo's youngest son)
- Colin Kintobor Jr./Snively (Colin's son)
- Hope Kintobor (Colin's daughter, Snively's half-sister)
- Johnny Snively
- Dr. Robotnik (Discovery Zone)
- Mayor Kintobor
- Dr. Ivo Kintobor
- Dr. Robotnik (Underground Version)
- The name Kintobor is "Robotnik" spelled backwards, and has played a role in a number of Sonic media. In early sources and Sonic the Comic, Robotnik/Eggman's name was originally Kintobor before an experiment gone wrong turned the kindly doctor into the malevolent Robotnik. In the Archie Comics, Kintobor was given as Robotnik's original name, which he seemingly reversed to create his new identity. When Sonic Adventure 2 made it clear that Robotnik was the family name of Eggman's grandfather, the storyline was modified so that Robotnik was the maiden name of Eggman's mother and that he took it in favor of his father's family name.