Which Assassin's Creed game introduced the playable Greek hero Kassandra?

Assassin's Creed Odyssey introduced Kassandra as a playable Greek hero.

Set during the Peloponnesian War in the fifth century BCE, Odyssey lets players choose Kassandra or Alexios as the playable character. Ubisoft later identified Kassandra as the canonical protagonist in the wider series continuity, while the game itself supports either choice for the player's campaign.

Kassandra is a descendant of King Leonidas I of Sparta and becomes a misthios, or mercenary. The story travels across the Aegean world and includes historical figures such as Pericles, Socrates, and Aspasia. Its role-playing structure includes dialogue choices, branching outcomes, naval exploration, and extensive gear systems.

Odyssey followed Origins and was released in 2018. It is set earlier than Origins, despite being released later, and should not be confused with Valhalla, whose story is set in ninth-century England.