Despite gaining an equal footing with abyssals, humans didn't even entertain the idea of invading the abysses.
The primary reason was the abyss will.
It had three very annoying functions.
If an enemy of higher-level was attacking a lower level abyssal and there's no equal or higher level abyssal in the vicinity, it'd inform the nearest qualified abyssal.
For instance, if a level 5 human attacked a town, governed by say, level 4 abyssal, then the abyssal will would inform the nearest level 5 abyssal.
The second function was its psychological suppression. Unlike Heaven's Will, it couldn't directly reduce the combat power of hostile units.
However, the psychological challenges it posed were a headache in the case of large-scale military operations.
What's more, the fiercer the conflict, the greater the mental suppression. This meant the combat units wouldn't be able to exert their full power.
