Incarnate: Book One of The Celestial Wars

The five provinces are prosperous, the people thriving. The only blight upon their society is the Hinterlands—the formidable forest that harbors bloodthirsty creatures and drives those within it mad. The forest protects the reason for Ithilia’s prosperity, The Well, an endless chasm of magic.
When summoned to visit the charismatic Lord Aldrich, Lorn learns of a secret task only he alone can complete. Enter the Hinterlands, reach The Well and come back alive. Lorn must use his skills as a hunter and his magical abilities to protect himself from certain danger and return to Lord Aldrich with the fabled magical item. What he learns and discovers will change the five provinces of Ithilia forever.

Content warnings: gratuitous violence and death; death of a spouse; depression