Doused - The White Warrior series, #4

Azrel has sent several of her companions across Casdanarus, and beyond, to recruit an army formidable enough to challenge Hathum's. But strong hatred for The White Warrior is still a major obstacle they must overcome. Meanwhile, the hunt for the Anarran Gem owner takes Azrel and her companions to the treacherous realm of Spar Ridges - a place where ancient Shadow creatures, many immune to modern-day magic linger and thrive.
Here, a deluge of Shadow waits to douse Azrel's magnificent Light, and someone more powerful than Hathum emerges as her enemy.