The hybrids were a humanoid species directly descended from those Isu who chose to interbreed with their human workforce. As a result of this interbreeding, hybrids were born without the artificial neurotransmitters that forced humanity's subservience to their Piece of Eden-wielding Isu overlords.
Over the subsequent generations, the hybrids and their offspring were assimilated into the general human population. Consequently, the concentration of Isu DNA in their own genome became diluted with each generation.
At some point before the 5th century BCE, the Order of the Ancients started referring to humans directly descended from the hybrids—and as such, the Isu—who possessed extraordinary skills and abilities with the epithet "Tainted Ones", despising these traits and considering such individuals as being "less than human".
During the 5th century BCE, some such individuals were recognized by the greater human population and believed to be direct descendants of the gods. Because of this, individuals like Kassandra and Alexios were often referred to as a "demigod", and revered as such by people like the Worshippers of the Bloodline, a branch of the Cult of Kosmos.
Certain bloodlines directly descended from the hybrids, however, possessed fractionally higher levels of Isu DNA in their genome, resting somewhere between the 0.0002% of normal humans and the 5 or 6% of Sages, which allowed their scions to naturally access Eagle Vision and to more fully interact with Pieces of Eden much like their ancestors. In the case of Sages, their high Isu DNA count meant that they could serve as a reincarnation of Aita or a member of either the Æsir or Vanir, two Isu groups who once lived together in Asgard.
Considering the abilities of people like Kassandra and the knowledge and abilities shown by the Sages, Adam and Eve were most likely extremely physically and mentally powerful. In the video file titled "The Truth", Adam and Eve were shown freerunning from ground level to the top of Eden extremely quickly.
Known "Tainted Ones"
- Assassin's Creed II (Flashback or repressed memory)
- Assassin's Creed III: Liberation (mentioned only)
- Assassin's Creed: Odyssey (as "demigod")
- Assassin's Creed: Infographics
- Assassin's Creed II – The Truth
- Assassin's Creed: Odyssey – Legacy of the First Blade: Hunted – Protector of Persia
- Assassin's Creed: Odyssey
- Assassin's Creed: Unity – Database: 05. Phoenix Project Report
- Assassin's Creed: Odyssey – The Fate of Atlantis: Judgment of Atlantis – Blood Gets In Your Eyes
- Assassin's Creed: Odyssey – Legacy of the First Blade: Shadow Heritage – Leviathan's Maw
- Assassin's Creed: Odyssey – Legacy of the First Blade: Bloodline – Legacy of the First Blade