Following the Ghost

There's a ghost that appears now and then, trying to interfere with our work. Have you seen it?
It looks like our spells awakened quite a few souls that were at rest in these ruins...
But our mission cannot wait!
Let's finish this. I'll give you an artifact that detects ghostly traces. You can use it to find traces nearby and follow them to the ghost's hideout. Find out what it wants. You're good at solving the dead's problems, so go!

You are looking at an old grave. Someone important is buried here. The epitaph is barely visible, but you can see fragments of words. "H..re r..sts G..len..l, a p..werful s..rcer..ss and k..eper of Vel..grad wond..rs."