The Spoils of Desecration

The Spoils of Desecration is a side quest in Dragon Age: Inquisition. The combined pieces make a key that may be used to open something likely important and certainly old.

Acquisition
A Key Piece in a grave.

Walkthrough
When in Var Bellanaris, destroy one of the graves. A demon will appear and fight. Take it down & loot the grave. Continue this until you have all 3 pieces.

Use the key to open the tomb door. Go through the room and up the stairs. When you loot the central urn, undead will start to rise, along with an Arcane Horror. Kill the ones in this room. Go back towards the surface and more will spawn in the first room. Kill them and your quest is complete.

Result
Keeper Hawen will admonish you for destroying the graves, but will not prevent you from completing By the Grace of the Dalish