Rise of the Dragon Impervious (The Kakos Realm 2)

Faith-based dark fantasy.
As Rashnir and his friends look for way to escape from Grinden, the demonic prophet Absinthium crowns the warlord Rutheir as King and ratchets up pressure against his enemies.

Their travel plans suddenly go awry while they await the return of one of the First Elves. The ranger and all of his friends find themselves trapped at the center of an old quarry and facing the unified armies of their enemies--even an army of the dead.