Aspasia

Aspasia, also know as The Ghost of Kosmos, is one of the main antagonists of Assassin's Creed: Odyssey (alongside Deimos). She is the leader of The Cult of Kosmos, a proto-Templar organisation based in Ancient Greece.

Biography
During the Peloponnesian War, Aspasia fell in love with the leader of Athens, Perikles. This gave her a high position in Athenian politics which also allowed her to lead the Cult of Kosmos.

By the time Kassandra has dismantled the Cult by defeating every member, Aspasia was confronted by her when she went to the Cult's lair in Delphi. Here, Aspasia claimed that she saw the Cult's corruption and try to destroy it by letting it hunt down Kassandra, and that then she would build a resistance to rid the Greek World of corruption. However, all this was a lie, and resulted in Kassandra fighting Aspasia, killing her.