In God of War, Cronos is shown with only four fingers. In later installment, he is shown with five.
Early screenshots of God of War shows Kratos' tattoo in the shape of the omega symbol on his head. Kratos' design had gone through several different changes in the games early development.
According to an interview with David Jaffe, Kratos' character was based off of Derek Vinyard from the film American History X.