If it were a normal time, upon encountering such a rare individual, the War God would most likely choose to issue a divine decree, even if it meant bestowing immortality as a price to have that human join the embrace of his church, spreading his name among the Mortal Realm.
But now...
"...There's no helping it, you can only say your luck is bad."
"Before this, I was still agonizing over which human to pick to play the role of Achilles. After all, he had fought against other mortals, and others knew of his power."
"I truly didn't expect that even fate would stand on my side today..."
"Hahahahahaha..."
With boisterous laughter, he soared into the air. Ares intended to quickly go and return, capturing that human before the people in this city noticed.
As for whether he can defeat him—what a joke, without the power of the Styx River and the assistance of a Divine Artifact, Achilles could not possibly defeat him.