To describe the land, you could send someone on a journey or quest.
Perhaps someone needs to find Karsh, but can only track him by his sojourns along the way.
Then you could have interesting folk tell of how things used to be, and perhaps how the passing of Karsh affected their change.
Or your traveler could be a quest-harvester, seeking to put the elements together for his songstory.
Hmm..
In the second, er, third book, Karsh starts out as a ghost.
Could be that the first ‘two’ are the narrated, sorta, tales of how he got to be a ghost living in exile in the Frost Wastes.