The protagonist of God of War: Ascension is Kratos.
God of War: Ascension was released in 2013 for the PlayStation 3. Although it was the seventh installment in the franchise by release order, its story is a prequel to the earlier Greek-era games. It follows Kratos after he has broken his oath to Ares and before he becomes the servant of the other Olympian gods.
The campaign focuses on Kratos's struggle against the Furies, supernatural beings who punish oathbreakers. This setting provides additional background about his rebellion against Ares and the events that eventually lead to his search for revenge.
Ascension also introduced a multiplayer mode to the series, allowing players to choose an allegiance to one of several gods. That feature does not change the identity of the single-player protagonist: Kratos remains the playable central character. The game is therefore part of his Greek mythology arc, not the later Norse story centered on Atreus.