While the full extent of what The Archetypes are is left a mystery, they are a group of people brought back to life possibly as one of Project Blackout's main objectives. The faction consists of Alex Mason, Frank Woods, Raul Menendez, Viktor Reznov, and presumably Jason Hudson and David Mason. It is not known if there are any other Archetypes brought back to life.
It is extremely plausible that The Archetypes are actually real and not reborn as A.I. with evidence from the Specialist HQ mode's intel and their respected calling cards. In "The Black Hole," "Raul's Way," "The Panama Suspect," "Kiss of Death," and "Dead Again" - each of the Archetypes (with the exception of Reznov) interact with Savannah Meyer, even physically.
Additionally, there is evidence to show that Project Blackout and the Blackout mode are both connected to further prove this claim's authenticity
In the Specialist HQ Intel file "The Running Woman," Battery says that "People are actually dying out there in the zone" and that she sees shapes, which Ruin corrects by saying they're actually numbers - Likely referring to the Collapse in Blackout.
In the Specialist HQ Intel file "Angel Heart," Menendez says that "Sites are under construction all over the world." In Blackout, there are some construction sites.
In the Specialist HQ cutscene "It's YOU in the box," Woods and Mason are at the Asylum from Blackout.