When fighting Ares in the final battle in God mode, Ares should first stick his sword in the ground and crush you with the four pillars. If not, keep evading Ares until he does. When Ares tries to crush you with the four pillars, roll toward Ares and let him have it with the sword. Use the L1 + Square combo then roll away from Ares. Ares will then start chasing you. Keep evading him until he tries to attack you. Then, go up to Ares and let him have it again by just pressing X. This is where your swords should clash and a mini game will start, where you have to simultaneously press Circle. If you win the mini game, you will take a good chunk of Ares' health. Then, repeat the process until Kratos is victorious.