Universe/Timeline:
Marvel Universe
During the rise of Operation: Zero Tolerance, Bastion commissioned the creation of the most insidious form of Sentinels yet. Prime Sentinels were human beings outfitted with integrated bionics and nano-technology, possessing all the power of a Sentinel mutant-hunting machine as well as the creativity and adaptability of a sentient mind. Many Prime Sentinels were also sleeper agents, innocent civilians transformed by OZT and unaware of their true nature until encountering a mutant, at which point their compulsive programming would kick in.