The second spirit linking

In class, every student just laid all over their tables, completely unable to mount any semblance of interest in the lesson.

While the old teacher completely ignored the circumstances and continued to recite from his book monotonously and mechanically.

"When the great tomb manifested, a rain of corpses and blood descended from above"

"The underground of our Tomb of Myriad Beasts suddenly manifested billions of bones and corpses that each gave off immense miasma"

"Fortunately, as we were the original inhabitants of this world, we were able to use our connection with the world to move through its natural barriers and traverse freely between the Grottos"

"Anybody from other worlds would only die by the miasma of those corpses"