What was the name of the Assassin's Creed game released in 2018 and set mainly in Ancient Greece?

The 2018 Assassin's Creed game set mainly in Ancient Greece is Assassin's Creed Odyssey.

Odyssey takes place during the fifth century BCE, around the Peloponnesian War. Players control either Kassandra or Alexios, mercenaries descended from Leonidas I of Sparta. The game explores regions of the Greek world, including Athens, Sparta, islands, and coastal settlements, while presenting historical figures such as Socrates and Pericles.

Ubisoft Quebec developed Odyssey, which launched in 2018. It expands role-playing elements with dialogue choices, branching quests, naval travel, gear management, and multiple endings. Although it is part of the Assassin's Creed universe, its story predates the formal development of the Assassin Brotherhood shown in Origins.

Origins is the 2017 game set in Ptolemaic Egypt. Valhalla is the 2020 Viking-era entry, while Mirage is set mainly in ninth-century Baghdad. These neighboring titles make the release year and civilization useful clues for identifying Odyssey.