ISOs have a glowing symbol on their arm and some depictions also show other markings on their skin. By the time of TRON: Legacy, Quorra is the last known ISO alive, after Kevin Flynn saved her from the Purge.Īfter Quorra left the Grid with Sam Flynn, no ISOs were thought to have remained in the system.Īll ISOs appear physically identical to humans and other programs, but there are some fundamental differences between ISOs and other beings. Subsequent to his betrayal, CLU initiated a genocidal assault on the ISOs which was later referred to as the Purge. As the ISO population grew, they attempted to integrate with the Grid's population, but met resistance from Basics, and thereafter formed their own colonies. Their existence was considered a miracle by Kevin Flynn however, CLU considered them to be an obstruction in his mission to create the perfect system. The ISOs were first discovered by Flynn and CLU in 1984 near Tron City.
This inner structure of their code would potentially have allowed ISOs to develop beyond the capabilities of regular programs. While regular programs conform to the rigid structure defined by their users, ISOs had evolved to become independent beings, complete with a genetic code of their own that even Kevin Flynn could scarcely comprehend.
ISOs differed from Basic programs in their appearance and capabilities, but their uniqueness lay in their codebase.