Old man power! Though he wasn't originally a usable character, the boys at Squeenix had enough foresight to add the mightiest old man to their US release, and the world is much happier for that! Despite his age, Adray is just as fit as the rest of the 'young-ins': hardened, calm, cool, collected, and extremely tenacious ( especially when it comes to finding his daughter a husband! ). None in Light can match his amazing talents, and his Light run so far has definitely proved that.
In the arena, Adray's knowledge of years upon years of battle is a significant aid. With mastery over magic and the sword, there's nothing that this old man can't do! Frustrated? Get stronger!