In Assassin's Creed Odyssey, Kassandra’s adoptive father is Nikolaos.
Nikolaos is a Spartan general known as the Wolf of Sparta. Kassandra is raised in his household alongside her brother Alexios, and the family’s traumatic history becomes a major part of the game’s central narrative. The player’s choices can affect how Kassandra’s relationship with Nikolaos develops and how the family story concludes.
Nikolaos is not Kassandra’s biological father. Her biological father is Pythagoras, an ancient Greek philosopher and mathematician who appears later in the story. Leonidas is Kassandra’s famous Spartan grandfather, while Brasidas is a historical Spartan commander encountered during the Peloponnesian War setting.
Odyssey takes place in Greece in the fifth century BCE, during the Peloponnesian War. Kassandra is the canon protagonist in later series material, although the game also allows players to choose Alexios as the playable character.