The first days were manageable.
Zhao established a rudimentary camp at the entrance. Fortunately, the tunnel offered protection and a clear view of the corridor for a good stretch, and it was empty. The mountain seemed to be full of passages and chambers reflected in the crystal, but exploring them without the king was guaranteed suicide for a Silver rank.
The mana mountains of the rings had high-level trials, beasts and natural traps that required real power to overcome. Or that had been the intelligence that Victor brought...
And not just that...
The underground Platinum Sprouts and other species couldn't enter, but there were high-level species that had entered at some point before the Dragons long ago and adapted differently inside here.
After a few days of tension, Zhao understood that the monsters inside the mountain didn't seem to move from their place.