Icy Grave CR 15
NE haunt (10-ft.-by-60-ft. tunnel)
Caster Level 15th; Notice Perception DC 30 (to see frost crawling up any objects touching the floor or walls)
hp 67; Weakness fire spells and effects (these effects damage the haunt); Trigger proximity; Reset 1 hour; Effect Rime and frost crawl up the limbs and clothing of every creature within the tunnel. Any creature within the area is affected by icy prison and must also attempt a DC 23 Fortitude save each round it is trapped in the ice or take 1d4 points of Constitution damage. Corpses that remain trapped in the ice for longer than 1 round are absorbed into the walls of the tunnel; reviving a character absorbed in this way requires true resurrection, miracle, or wish.
Whispering Wisagatcak (CR 14): A wisagatcak lurks within the icy caverns of Frozen Tears, lured in by the kytons’ many helpless victims, who have no means to escape the wisagatcak’s insidious whispers. When the wisagatcak notices the PCs, it begins to stalk them, using its natural stealth and spell-like abilities to stay unseen while it attempts to drive the PCs insane. The wisagatcak follows the PCs so long as it can remain hidden, but prefers to avoid a direct confrontation unless the PCs look exceptionally weak.
Pathfinder Adventure Path #137: The City Outside of Time © 2018, Paizo Inc.; Authors: Amanda Hamon Kunz, with John Compton, Gregory Hanigan, and Mikko Kallio.