Entity 55, also known as The Howler appears to be a large, white humanoid entity with two glowing white or red eyes, approximately 4,2 meters tall, with 3,1 meters long arms and legs. It appears to possess large, sharp claws at the end of both its arms. The entity's feet appear to be 'flat' although it does share some similarities with normal human feet. The entity also possesses a large, red 'circle' at its torso seemingly resembling blood. It is presumed that this is an intimidation tactic used by the entity. The entity's claws also have similar red-colored shapes.
The entity doesn't appear to possess any type of body hair, and its appearance is described to be simplistic. The skin of the entity is 'odd' as it does not have any reflection and appears like it had multiple skins over it, however, further investigation reveals that the entity only has 1 layer of skin.
Recovered and cut audio from M.E.G. of The Howler speaking.

The Howler figure seemingly disappears whenever it enters dark areas, and only its 2=two glowing eyes will remain apparent. It's also known that it can blend in with the environment, as its skin can change color to fit with the environment around it to hide from danger or to hunt wanderers.

The Howler's most characteristic property is its ability to mimic human voices, the voices it makes will always be male young voices from people around 17-24 years old, but there is a clear difference between normal human voices and the ones that Entity 55 makes. The voices that the entity makes feel 'odd' and are not completely similar to a real human voice, but wanderers that have spent days or even months without any other human company, may not notice this. The speed and strength of Entity 55 are abnormally high, as it can easily outrun human speed if a chase occurs.

Behaviors

The Howler will be most likely lurking around corners of hallways or walls that are oddly placed, like the pillars found in Level 1; therefore it is easy for them to go unnoticed when they are near a human. If they are not around any walls, then they may be hiding inside the dark areas in levels where there are no Smilers or any other similar entity.
The method of how the entity attacks wanderers is to mimic human speech to attract wanderers to their location, once they are near enough if the wanderer does not notice the entity; The Howler will then use his claws to attack the wanderer's eyes and blind them to later throw them to the ground and start eating them while they are still alive, but to not make noise, the entity will cover the victim's mouth. Anything that happens after this is unknown. If the wanderer notices the entity before they are attacked, then the entity will chase the wanderer while emitting a loud screaming similar to a human in extreme pain, but it will be extremely 'odd' and won't feel human at all, after that the entity will probably outrun the wanderer and kill them by chopping their head off.