He was created in the distant past by Professor Niven Clarke and was subservient to Dr. Ivan Kintobor. Activated when the Xorda aliens launched their first assault on Mobius, he monitored Kintobor while he was in stasis in his bunker. He is an Alpha 100 Series Mechanoid built over 10,000 years ago. He has a head of Development Team, Doctor Ivan Kintobor, a hardware designer Professor Clarke and software programmer Doctor Niven.
Rediscovered by Shadow the Hedgehog and Metal Sonic in the present day, he recounted his experiences of observing history from afar, including the first conquest of Mammoth Mogul and the coronation of the first king of the House of Acorn. He joined Shadow in battling Metal Sonic and Sonic, but was left to his task. Dark Legion rogue Dr. Finitevus was later revealed by Rouge the Bat to have stolen some of Isaac's data. However, Isaac's data had become quite corrupted over time, to the point that he didn't even realize that he was guarding Kintobor's corpse. Because of this, much of the info held by the robot is dubious in terms of accuracy.
- Isaac is named after science fiction author Isaac Asimov, just as his creators (Clarke and Niven) are named after science fiction authors Arthur C. Clarke and Larry Niven.
- Head writer Ian Flynn has listed Isaac on his list of deceased characters, indicating that Isaac will not be returning.