Considering the issue of identity, Anvis uses only the Domain Power of the King of Nightmare Spirits himself, and does not employ other means; however, that does not mean the strength he exerts is significantly weaker.
As the concentration of the dark side of the Inheritance Land, the power of the King of Nightmare Spirits is essentially very strong. The reason the struggle with the girl is so arduous is solely because Fiona's power is even more unreasonable.
After all, being the finest creation of the two major families of the Empire, though Fiona's displayed strength surprises Anvis, it is not unexpected.
If she couldn't even reach this level, how could she shoulder her destiny in the future?
Seeing that the domains of both parties were at a standoff, Anvis's gaze flickered slightly, and he immediately employed the backup plan he had prepared earlier.