Walking to the center of the underground space and looking up, Gu Xi happened to see the perfectly vertical passage.
The passage was quite enormous.
Looking up from more than sixty meters below, he could still see a massive shaft over forty meters in diameter.
Given the size of this passage, two or three dragons could easily fly through it side by side.
Looking farther up, he could even see a faint bit of sunlight filtering down.
Clearly, this passage led directly outside the castle above.
All the dragons could fly out through here, while sunlight and rain from above could also fall into the underground space.
Directly beneath the passage lay a gigantic Labyrinth.
It was different from the labyrinths between the City Walls he had seen before.
The Labyrinth before him was entirely built from black square bricks.
These bricks were obviously much thicker and sturdier than the yellow bricks on the surface.
At the same time, Gu Xi noticed that traps, scattered gold, and bones left behind by unknown people could occasionally be seen within the Labyrinth.
Standing outside it, Gu Xi had the feeling that if he were not the master of this city and had no one to guide him, he might never find his way out after entering.
Even Pathfinding would be useless.
This Labyrinth possessed the ability to counter Pathfinding.
But as long as he did not enter, there was no problem.
Watching from outside, Gu Xi could tell that this massive Labyrinth was a large area combining seven or eight structures, including a labyrinth, reversing intersections, reinforced labyrinths, and more.
Some of these structures increased Minotaur Warrior production, some raised their levels and combat strength, and some provided equipment for them.
Every week, thieves would also be spawned inside for the Minotaur