Gwenaewen has bidden you challenge an ancient spirit as a test of quickness in the Wild Hunt that the Huntsman has set before you.
'You would take up the Wild Hunt, ${PLAYER}?
'I warn you that it is not for the faint of heart -- but if you would complete it, you must face an ancient beast, fast as the wind and of a tempest's mood. Seek it out, if you will, in the heart of the Mournshaws and challenge it.
'I shall await your return here, should you survive.'
Gwenaewen's spirit dwells in the heart of the Mournshaws.
Gwenaewen has charged you with hunting her falcon-spirit servant.
Gwenaewen is at the Huntsman's Hall.
You should return to Gwenaewen and tell her that you have overcome her challenge.