Which Assassin's Creed game introduced the playable Eagle Bearer Kassandra?

Assassin's Creed Odyssey introduced the playable Eagle Bearer Kassandra.

Odyssey is set in Ancient Greece during the Peloponnesian War, beginning in 431 BCE. Players choose between Kassandra and Alexios as the playable mercenary, but the game's novelization and later series continuity identify Kassandra as the canonical Eagle Bearer. She carries the Spear of Leonidas and becomes involved in conflicts involving Sparta, Athens, the Cult of Kosmos, and the First Civilization.

The game emphasizes role-playing choices, dialogue options, branching quests, and exploration across the Aegean world. Unlike many earlier entries, it does not center on a traditional Assassin Brotherhood, since its story predates the organization's later historical form.

Kassandra is sometimes confused with Aya of Alexandria, another major female character in the franchise. Aya belongs to Assassin's Creed Origins, whereas Kassandra is the canonical protagonist associated with Odyssey.