Hercules and Kratos are much alike. They both killed their wife and kids under the influence of gods, they're both sons of the greatest god, Zeus, and they're both champions in the arena. The only thing that makes them different is that Kratos can beat the crap out of Hercules. This boss battle walkthrough should teach you not to mess with Kratos or he'll beat up that pretty thing you call your face.
Watch the following on how to beat Hercules in God of War III.