C100 Surprisingly a black rune appeared suspected to be the dark mountain art!

I didn't quite understand the old professor's words. At this moment, the student next to me also asked, "Are you seeing things? There aren't any black characters here!"

No?

How is that possible?

I clearly saw it!

I asked the other students, and they shook their heads and said nothing.

Am I mistaken? That's not right. It seems like there is!

Suddenly