The corridor had come to an end.
A tall dark-red wooden door slowly opened, revealing the pitch-black world outside.
Su Shijun tightened her cloak and followed behind Gongsun Bing, slowly stepping through the door and onto the highest point of Black Prison Castle, the outer fortress tower, surrounded by battlements.
As far as the eye can see, the sky was dim and the view open. Above her lay a desolate world, where several distorted flashes of lightning occasionally appeared in midair and vanished in an instant, faintly revealing the formidable Qi Mechanism of layer upon layer of Guardian Formations.
Dense rune arrays covered the ground beneath her feet, linked together. In the distant base fortresses stood several towering figures hundreds of meters tall, their backs to the tower. From where Su Shijun stood, she could see only the backs of their heads, each shrouded in halos of light.
They were the Archwizards stationed at the base fortresses.
Hunting parties would occasionally climb along those Archwizards' arms and robes, patrolling in every direction and dealing with their minor afflictions, like oxpeckers picking Parasitic Worms off rhinoceroses.
This was Black Prison Castle.
The wizards' largest stronghold within Black Prison.
The location of the Xuanhuang Wood.
And the main battlefield where war was about to erupt.
To protect that ancient and miraculous plant, First University had established a complex, massive, layered defense system around Black Prison Castle. The entire system was divided into three layers, from outer to inner.
The outermost layer was called the "outer fortress." It consisted of three base fortresses and one tower. The base fortresses surrounded Black Prison Castle in an equilateral triangular formation, positioned at the triangle's three vertices; the tower stood directly above Black Prison Castle, occupying its highest point.
To put it more vividly, the entire