The plan was risky. But Emeros decided to play with strengths.
His power was in the mystery of Vasilius. And he didn't know how to actively use these powers other than being able to find incredible relics which demand spells, incantations, or be a legacy inheritor of an item.
With foe close to a Champion, this was the safest way that Emeros could think of.
Emeros decided that the only way he could defeat someone as strong as this was to make a vow with it that would be to their benefit.
But Emeros knew that there was a strict rule that his vow had. He could not move against a vow but only follow what the vow states. There was a strange honor that he had to uphold by fulfilling his end of the vow. Just like the other vows that Emeros had, he could only take advantage of those who tried to make a breach of contract or enforce a Contract of Unequals.
