Wall Blisters are large, bulbous creatures that vaguely resemble barnacles. Most of the time they will stick to walls and ceilings, appearing as little more than swollen blobs of flesh. However, when disturbed, they detach from the surfaces they cling to and reveal their full forms, which appear humanoid. They have two arms and two legs made of slick, rubbery flesh and their arms end in several boney spikes that better allow them to grasp and maul prey.
It is unknown exactly how the Wall Blisters were created, though it is suspected that they were born from a colony of barnacles found attached to the bottom of a swimming pool in the Queen Zenobia's Solarium. The barnacles grew in size to the point where they ruptured the pipes distributing water to the pool, causing the T-Abyss virus to flood in and contaminate them.
When attached to walls, Wall Blisters pay no attention to what goes on around them. When they detach, they will charge at prey ferociously with frightening speed, attempting to grab their victims and crush them with their powerful arms. Despite their strength and speed, Wall Blisters are actually quite fragile and can be killed with a burst of automatic fire so long as distance is maintained.