An ancient life form by the name of Kutum. The Ancient Fragment stuck in its body functions as a heart.
According to old records, Ancient Kutum used to live inside the Scarlet Sand Chamber. The chamber's doors were shut tight as soon as Kutum stopped moving, which then led to the chamber's mysterious disappearance.
The thundering sound of Ancient Kutum's heart recently re-opened the doors of the Scarlet Sand Chamber, and its entrance was discovered by archaeologists and explorers.