To be exact, the Chaos Power was useful, but the status of Youri was.

As the elder of the Doom Race, Youri had high prestige in the Greater Realms. Thus, the Bug Race dared not offend him. Offending him was equivalent to offending the Dooms.

If the Dooms became angry, the Bug Race would be wiped out easily. Nevertheless, James was able to succeed in acting as Youri because of the Chaos Power.

His Chaos Power was not weak. It was powerful. Even though he had not reached the Acme Rank, he had s