Wall Dwellers are humanoid monsters lacking arms with a set of flat plate-like coverings on its front to camouflage into walls. Wall Dwellers have no discernible eyes or other bodily features, besides human-like mouths with split lower jaws and sharp teeth.
Mechanics
Wall Dwellers act as an ambush predator, and will emerge quietly from walls in previous rooms and advance towards players, attacking them once they gets close enough. If spotted, the Wall Dweller will cease hunting and run away.
Notes
Wall Dwellers can be killed by node monsters, resulting in their corpse being left on the ground after an attack.
It is said that these corpses will be able to be eaten by player in the future, effectively giving the consumer the effect of a Party Special.
Wall Dwellers will exit their hiding spots in the previous room right after the player enters the next room.
It is possible to spot Wall Dwellers by looking closely at walls, as they break up the material patterns and have a slight outline.
There is a 1/80 chance for a Wall Dweller room to spawn as the next room.[1]
Wall Dweller rooms are easily identifiable if the player has the console open.
Wall Dwellers behave identically in The Ridge, but are much less of a threat due to the high prevelance of The Angler and its variants.
Strategy
Spotting Wall Dwellers can be made easier by keeping track of the number of footsteps being heard at any given time, and sticking closely together if in a group. Occasionally looking behind you can also help to scare off Wall Dwellers before they get too close.