In the game, the blessing that he received from the goddess Athena was one of his aces. It was a great help to every big battle that Souta faced in the game. Without it, he wouldn't be able to win most of his battles.
When he was fighting the demons, the commandments, the deadly sins, and the zodiacs the blessings greatly helped him. Even though he wasn't at their level the blessings helped him shorten the gap in their powers.
He wouldn't be able to fight them in a one on one battle. Several huge countries would work together just to subdue a single person from the bringer of calamity.
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