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A component of Site-111's ventilation system prior to SCP-4370's anomalous properties manifesting.
Item #: SCP-4370
Object Class: Euclid
Special Containment Procedures: A 1 km2 perimeter has been secured around Site-111 to prevent unauthorized entry. Only Level-4/4370 clearance personnel are permitted beyond said perimeter. Personnel who enter the perimeter are to be equipped with a gas mask to prevent SCP-4370-2's anomalous effects.
Any and all entrances and exits to SCP-4370 have been sealed off by concrete with the exception of one entrance which has been secured behind a small airtight chamber. Under no circumstances should any individual attempt to enter SCP-4370 aside from authorized exploration drones and pre-selected D-Class personnel. Any individuals or devices which have entered SCP-4370 are not to be recovered and should be considered MIA.
Instances of SCP-4370-1 are currently considered self-containing due to their refusal to voluntarily exit SCP-4370. Should an SCP-4370-1 instance exit SCP-4370, they are to be recovered for immediate containment.
Description: SCP-4370 refers to the entirety of Site-111's ventilation system.
SCP-4370's primary anomalous property is the constant alteration of itself without altering Site-111 nor any constructs around it.1 SCP-4370's alterations have been noted to submerge deeper than levels of human habitation due to extreme temperature. Other than its large size and constant shifting, SCP-4370 itself holds no additional anomalous properties.2
SCP-4370 is inhabited by a variety of organisms deemed SCP-4370-1 collectively. The majority of SCP-4370-1 instances have a vaguely humanoid, snake-like anatomy,3 with other instances being physically identical to multiple unidentified species of snake and tarantula. SCP-4370-1 instances have only been noted to display signs of fear and/or curiosity followed by hostility. They have been noted to violently attack personnel and man-made devices which enter SCP-4370.
SCP-4370-1 instances, when frightened, emit an unidentified yellow gas (SCP-4370-2) from their pores. When inhaled, subjects display symptoms of fever, migraines, and hallucinations (ranging from 5 minutes to 24 hours) followed by spontaneous human combustion.4
Notably, SCP-4370 displays signs of sentience. Further investigation is ongoing.
Addendum 4370.1 - Discovery: SCP-4370 was recovered following Site-111 personnel reporting "odd sounds" from the ventilation shafts and a "thick yellow gas" exiting said shafts in apparent intervals.
The following is the transcript of an administrative call to Site-02:
[BEGIN LOG]
Ken: This is Site Manager Ken.
Tut: Hello? Yes, this is Researcher Tut working at Site-111. We've, uhm, we've got a problem. There's been a gas leak or something. It's.. it's everywhere.
Ken: What? Do you need an MTF?
Tut: Yes, uhm. I don't know what's happening but my head hurts…
Ken: A mobile task force is currently on the way.
Tut: The vents are creaking.
Ken: Irregularly?
Pause.
Tut: …like a frog sitting lonely in the pond, its mucus glistening in the moonlight…
Ken: Researcher Tut, are you there?
Tut: Yes, sorry. It's just..
Pause.
Ken: Just what?
Tut: What?
Ken: Researcher Tut, can you hear the words I'm saying?
Tut: Yeah, uh. Yeah, yeah I can.
Ken: I need you to gather as many people as you can and exit the site immediately.
Tut: The creaking! There it is again! Can you hear it?
The audio picks up no sound.
Ken: …no?
Tut: I'm telling you, I didn't do it!
Ken: Tut?
Tut: The walls— they're closing. Shrinking. Coming to me.
Ken: Tut, what is going on?
Tut: I don't wanna die.
Ken: You're not going to. Talk to me, they're almost there.
Tut: What? You're… you're not here to kill me? But, if you aren't, the— the walls will! Stop them! Please!
Ken: Tut?
Tut: [Calmly] I don't like snakes.
The line is quickly cut.
[END LOG]
Afterword: Researcher Tut was officially declared missing following this event.
The following is a video log of Mobile Task Force personnel upon arrival to Site-111.
[BEGIN LOG]
[The four MTF agents arrive at Site-111. The gate to the containment site was discovered locked. Authorization to breach the wall to the containment site was granted. Following the destruction of Site-111's security gate entrance, the MTF agents noticed no irregularities.]
Agent Petro: Let's move.
Agent Tick: Copy.
Agent Wjerluvski: Right.
[The agents arrive at the entrance to the underground containment area of Site-111. Notably, the entrance was already opened.]
Agent Tick: That's… weird.
Agent Lex: We listened to the distress call, and you think the door being opened is weird?
Agent Wjerluvski: What he meant to say, I think, is that it's something to note that the door is open.
Agent Lex: Hmph.
[All four agents begin to descend the main flight of stairs to the containment area due to the transport elevator not working.]
[Two minutes of irrelevant dialogue has been skipped.]
[The agents reach the containment area of Site-111. The interior of the facility looks very worn and damaged.]
Agent Petro: Do you guys smell that?
Agent Lex: What?
Agent Wjerluvski: That. You don't smell it?
Agent Lex: No?
Agent Tick: Whoo, that's.. that's bad.
[Agent Tick places his gas mask on. Following the other agents noticing, they do the same.]
Agent Wjerluvski: Why haven't we seen anyone? Nor anything?
Agent Petro: I don't know.
[Above the agents, a heavy scurrying sound can be heard alongside a high-pitched squeak. This event particularly frightens Agent Lex, who immediately flicks the safety off to his firearm.]
Agent Lex: [Suddenly] Woah, shit!
[The rest of the agents quickly turn off the safety to their weaponry and aim at the hallway's ceiling.]
Agent Petro: That's the vents. No way it isn't.
Agent Tick: How do we know for sure that it's the vents?
Agent Petro: Because we just walked down the stairs, and I didn't see a second floor.
Agent Wjerluvski: Metal banging, also.
Agent Petro: [Hesitantly] Stay frosty, boys.
[The agents advance down the slim corridor until they come across a room with an unusual amount of vents.]
Agent Lex: What in the hell…
Agent Wjerluvski: Look, guys. Gas.
[Agent Wjerluvski points to one of the vents revealing a thick, yellow gas pouring out of it at an extreme rate.]
Agent Tick: Never seen anything like it.
Agent Petro: Neither have I.
[A sound which sounds like an adult male crying can be heard from the same vent in which the gas is exiting. Agent Lex points his weapon towards the vent and the others aim their weapons in random directions around the room.]
Unidentified: [Unintelligible]
Agent Wjerluvski: Identify yourself!
Unidentified: Researcher T- [unintelligble] Founda- [unintelligible.]
Agent Petro: What the fuck is going on?
[SCP-4370's anomalous properties begin to manifest as the ventilation shafts appear to "grow," expanding out from the wall in odd directions and formations. The same high-pitched squeal heard earlier is audible once again.]
Agent Tick: Jesus fucking Christ!
Agent Lex: Fuck, let's go, what are we doing!
[One of SCP-4370's expanding shafts quickly dashes forwards as it autonomously opens, consuming Agent Lex. The only sound audible for five seconds is a combination of screaming, gunshots, and wet tearing followed by loud splashes of thick liquid.]
Agent Petro: Fuck! Go, fucking go!
[The agents are seen running towards the stairwell to enter/exit Site-111's containment area but is suddenly blocked as a large ventilation shaft expands, causing a massive hole in the opposite wall.]
Agent Tick: Fuck, I'm gonna die, I'm gonna—
Agent Wjerluvski: We will get out of her, brother. No one is dying today.
Addendum 4370.2 - Exploration Attempts: D-4370-1 was selected to conduct a human exploration of SCP-4370. D-4370-1 was equipped with both a head-mounted camera broadcasting to the local research team and a functioning headset.
[BEGIN LOG]
The video begins as D-4370-1 enters SCP-4370.
