Aranea Membri, also known as Spider Legs, are fast moving, predatory entities which inhabit several levels of the Backrooms. These entities are named after their black, spider-like legs which seems to absorb all light and "meld into the shadows" when emerging and disappearing through holes in the ceiling. These entities are also infamous for the metallic clanking sound they make when chasing after you.
Description
Aranea Membri are said to measure approximately 7 ft in height and 8 ft in length, though their exact size remains unknown as they are too fast to be observed closely. These entities will always emerge suddenly from the ceilings of indoor levels, and proceed to chase down Wanderers in an attempt to trample under their limbs.
When hunting, Aranea Membri are able to reach speeds of up to 50 mph, though it is only able to reach these speeds in levels with long enough hallways. Aranea can also use their momentum to knock over obstacles and break down walls, or instantly crush their target. After a successful hunt, these entities will drag the victim through the hole from which they emerged and disappear from view. To date, no Wanderer has dared explore these holes in the ceiling.
A Aranea Membri Descends from the ceiling.
Weaknesses
Despite their otherworldly appearance, Spider Legs are ultimately nothing more than wild animals, and susceptible to mortal wounds and sickness same as any other creature. Carefully-planned traps and mundane weaponry are enough to terminate a specimen, as demonstrated by anonymous researchers (here). The high velocity speeds they produce are indeed a danger, but Wanderers can easily make use of sharp turns to force the Spider Legs' to slow considerably. Their low intelligence also shows that they are quick to forget prey once out of sight for 1-3 minutes standard time.