The Vault of Avial

About It
Although the vault of Avial looks like it was once a tower there is no stairs or floors to the upper part of it, just a hollow set of wall, why this is no one can work out but some believe it was meant to help see it through the trees although it is no longer surrounded by the forest, it is still near the trees.

It was built by the reapers as storage for used soul gems, a single reaper set to stand guard over it for all time sealed in a soul gem himself to be freed if the doors should ever be opened again.

The tower actually extends underground, a long tunnel that splits into three, each ending in a circular room, each laid out the way. A central pillar with slight indents where the gems were places, the ground marked with grooved rings like the rings of a tree stump.

History
When humans arrived on Avial, the vault was the only building standing; though the tower was in a bad way and the area was a mess, bones of long dead people, trees having grown and broken bits of buildings around it. They cleared the area and investigated it but never managed to get it open. 

      It remained a curiosity and unopened till very recently when a stranger appeared that knew how to open it, letting out what was contained within it.