C3814 Oligohypersensitivity

The Sky Cavern was the name of a immortal crystal mine within the Ancestor Mountain Range. This was an old mine that had once dug out extraordinary things.

There were rumors that over a decade ago, someone had dug out a living being from the Sky Cavern that had been sealed inside the immortal crystal's ore.

There were also people digging out peerless immortal sources in the Sky Cavern