The Ghost King — R.A. Salvatore

When the Spellplague ravages Faerûn, Drizzt and his companions are caught in the chaos. Seeking out the help of the priest Cadderly -- the hero of the recently reissued series The Cleric Quintet -- Drizzt finds himself facing his most powerful and elusive foe, the twisted Crenshinibon, the demonic crystal shard he believed had been destroyed years ago.