Transforming into human form, speaking the Human Race language, using Human Race characters and runes, that is the highest tier of demon.
The four Demon Emperors are also like this; their normal forms are human.
Due to the issue of the Wanmu Mountain Range's ownership, the Four Great Demon Emperors gathered at Ten Thousand Eyes Peak in the Wanmu Mountain Range.
This mountain peak is thirty thousand feet tall, located at the center of the Wanmu Mountain Range, and is the highest peak among the mountains.
Because of the Ten Thousand Eyes Demon Emperor's unique preference, the surface of Ten Thousand Eyes Peak is devoid of any vegetation, and countless enormous protruding eyeballs are carved into the smooth mountain.
These eyeballs are even painted with Celestial Killer Golden Light. From a distance, the mountain appears to be covered with giant golden eyes, each golden light flashing chaotically, invoking terror in the beholder.
