You trudge alone through the knee-high water, weary of the darkness surrounding you, as you read through M.E.G. documentation on your phone for information relevant to the level you've found yourself in.
The Crawlspace Creature? Well, this looks like a crawlspace, sorta. It'd be best to read that.
Entity Number: 53
Habitat: The Insulation
Description
The Crawlspace Creature is a vaguely humanoid being standing roughly 7 feet tall. It has short rear legs that it walks on when not alerted to nearby prey. The Crawlspace Creature has two long claw-like appendages in place of arms, which it uses to drag itself quickly along the ground when pursuing prey. These claws are incredibly dexterous, and as such, it can impale prey swiftly upon them when it reaches them, killing most wanderers instantly.
While its combat abilities are daunting, The Crawlspace Creature displays very limited intelligence and a weakened sense of sight, possibly due to the dark environment of The Crawlspace. It primarily navigates via sound, only using its sense of sight to locate and quickly finish off its quarry when it has reached them.
You merely skim the behavior and biology portions of the page. As expected, it's mostly specific measurements and estimates as well as what is stated in the description with a bit more detail. Perhaps it might be an interesting read if you weren't more concerned with your own survival right now. You reach the part you're really interested in: the survival guide.
Survival Guide
Excerpt from Wanderer's Guide to the Backrooms vol. 3
While The Crawlspace Creature may be rather freaky, there's little to worry about most of the time. It's only been reported in The Crawlspace area within The Insulation. It hasn't even been sighted in The Deep Insulation.
If you're not in The Crawlspace, you've nothing to worry about. If you are, just keep quiet. No worries.
All reports concerning The Crawlspace Creature or information regarding it are to be sent immediately to an available M.E.G. officer for review.

M.E.G. - Bettering Humanity
You breathe a small sigh of relief, though not too loud. While you do wish you could make a bit less noise sloshing through this water, it's a relief to hear you're not in immediate danger, even if it is a bit hard to believe.
You recall from the documentation of The Deep Insulation, where you are now, that caches of rare supplies could be found here fairly deep in. Perhaps if you're lucky, you'll find a small crate of something valuable and get out of here with a bit more to barter with.
There's a subtle noise of more water being moved out of the way as if by footsteps from nearby that doesn't seem to synchronize with your movements. You freeze and listen.
…Nothing. You move forward a bit more cautiously and double check the documentation for The Deep Insulation as you walk deeper in. You find an addendum added to it, a log of expeditions that were sent to recover the rare and valuable resources stashed in the sublevel.
Expedition Number: 1
Crew Sent: 3
Distance to Supply Cache: 200 meters
Note: None
Expedition Number: 2
Crew Sent: 4
Distance to Supply Cache: 1 kilometer
Note: None
Expedition Number: 4
Crew Sent: 6
Distance to Supply Cache: 3 kilometers
Note: It was determined at this point that supplies were becoming scarcer, though the reason why is not yet clear.
Expedition Number: 5
Crew Sent: 5
Distance to Supply Cache: Unknown
Note: Expedition 5 unexpectedly lost radio contact several hours after leaving the outpost. No members from Expedition 5 have returned at the time of writing. Future expeditions have been halted while these disappearances are investigated.
You stare at the screen in confused disbelief, continuing to move forward as you contemplate this new information.
Your attention is suddenly drawn away as you find a supply cache on a small island where the concrete floor rises just enough to break the surface of the water. You investigate it curiously. You must've been wandering for several miles by now. A couple Level Keys, two bottles of Almond Water, a slab of Royal Rations, and a vial of Liquid Silence.
An absolute jackpot.
What could these invaluable supplies be doing way out here?
Then it clicked.
The sound of water being disturbed by quick, lunging motions grows louder behind you.
The Crawlspace Creature is not nearly as dumb as we thought.