MTF Epsilon-11 (“Nine Tailed Fox”) arrived at Gate C of Site 104 at 21:22 local time. MTF members involved were E11-1 (Squad Leader), E11-2 (Second in Command), E11-3 (Organics specialist), E11-4 (Psionic operative) and E11-5 to E11-9 (Squaddies). Site power is sporadic, and command are unable to communicate with Epsilon-11 due to the site’s subterranean construction. All following audio and footage were recovered from the MTF’s PRDs.

E11-1 (SL): This is Squad Leader. We’re beginning the operation. Any questions before we begin?

E11-6 (Sq): Orders on engaging affected staff?

E11-1: Do not engage unless provoked. If someone pulls a gun, you’re clear to fire.

<MTF Epsilon-11 proceed through Checkpoint C, and enter the entrance zone of Site 104. The entire above-ground staging area is devoid of any other individuals.>

E11-5 (Sq): Looks like the area’s-

<An individual later identified as Doctor Harvey, appears from the inside of Checkpoint C and throws an IED at the group. He is immediately terminated by E11-3, but the IED explodes, resulting in minor lacerations along E11-4’s legs and torso.>

E11-8 (Sq): Shit!

E11-2 (SiC): T███! Are you okay?

E11-4: I’m good, I’m good; just a few cuts.

E11-5: Eyes up! I see movement in the main ops room; take the checkpoint!

<E11-5, E11-2 and E11-9 break into Checkpoint C, and sweep for hostiles. They encounter D-3416, who promptly assaults E11-2 with a knife. D-3416 is easily subdued by the three agents and pinned against a wall.>

E11-2: D-3416! What is happening in this facility?

D-3416: <Unintelligible.>

E11-2: D-3416, tell me what happened. What happened to the staff? What happened in Site 104?

D-3416: <Unknown, repetitive statements; appears to be an as-of-yet unencountered proto-Uralic dialect. Continues talking over E11-5.>

E11-5: Just shoot him. We’re not getting anything out of this guy.

D-3416: (In modern English) Alive! I’m alive… Iahel, am I you? I see six Angels. They are so beautiful. Alaggada! The Hanged King watches me. My eyes burn, please! No more metal, no more steel! I will be god, always be god! Always always have been will be was being!

E11-1: Nothing useful. Terminate the D-class. We can’t leave a psionic anomaly out here.

E11-2: Got it.

D-3416: When was I? Why won’t time stay st-

<D-3416 is terminated by gunshot.>

E11-2: Is the rest of the checkpoint clear?

E11-9 (Sq): Yeah. Found a dead guard up top. Looks like the poor sod was trying to warn us.

E11-1: Figures. Alright, we’re done here. Move up, keep your eyes peeled.

<MTF Epsilon-11 proceeds past Checkpoint C, and advances toward Site 104’s aboveground superstructure. No further personnel, living or otherwise, are encountered during this period. E11-1 approaches the main entrance to Site 104, and attempts to open the blast doors. His authorisation card is accepted, but the entrance remains sealed.>

E11-1: I can’t get in. The doors won’t budge. Squaddies, get the charges. We’re breaching.

<E11-9 and E11-8 prepare thermite charges, and place them against the centre of the door. On E11-1’s mark, they breach. An enormous amount of steam is generated, greatly hindering visibility.>

E11-1: Clear the smoke, we’re heading in.

<Epsilon-11 enter Site 104. The entrance foyer has been overtaken by a growth of organic connective tissue, with a significant area of charred material near the main gate. The structure is porous, and continually releases large amounts of steam, creating a hazardous quantity of heat.>

E11-7: This place is disgusting. Any idea what this… meaty shit is?

E11-3: Looks like epithelial tissue, like you’d find in a stomach.

E11-4: Ugh. Gross. Any idea where the staff are? I can't sense anyone besides us on this floor.

E11-1: We don't know what happened. Judging by the halls, we can't assume anything good. Watch out for more hostiles. -4, track any psychic signatures. Tell us if something's up.

<Epsilon-11 continue through the facility. Beyond the entrance is the foyer of Site 104, which has been completely overgrown by the same growth noted earlier. There are several bright red pustules located around the room.>

E11-4: Clear. Can’t feel anything. Either nobody’s around, or the skip’s messing with my head.

E11-1: Understood. -3, any idea what those lumps are?

E11-3: Taking a look.

<E11-3’s mounted camera shows a close-up of the pustules on the wall. There is a partially formed human inside roughly matching the description of Site Director P████ ██████. Her head has several missing patches of skin, as well as a significant portion of her lower jaw. She appears to be unconscious.>

E11-3: What the hell? Come over here, there’s people in there!

E11-9: Oh, that is just… sick. Is that the site director in there?

E11-1: Cut it open, carefully. We might be able to get something out of her, provided she's still alive.

E11-5: On it.

<The team moves to a safe distance, while E11-5 uses a long-range laser cutter to ablate the material away. Several seconds in, the growth suddenly expands and bursts, showering the team with pus. The individual within emerges, revealing several deformities and physiological amorphisms, including elongated misshapen limbs, deformed facial proportions and an overall height of ≈250 centimetres, which was not initially apparent when Epsilon-11 examined the pustule. It turns to face E11-8 and leaps onto her, crushing her abdominal areas. E11-8 ceases lifesigns presumably due to fatal rupture of her organs.>

E11-2: It's hostile, take it down!

<Epsilon-11 shoot the anomaly (T-1), and successfully incapacitate it. E11-9 and E11-3 immediately run toward, and subdue the instance. Despite the loss of its left arm, an incomplete jaw and severe damage to its abdomen (including the severance of its lower spinal cord), it continues to struggle and articulate.>

Site Director P████ (T-1): Stop! Stop! You’ll kill us! You killed me!

E11-4: Jesus christ! You killed E████!

E11-1: Quiet for a moment. -3, hold its arms down. (Speaking to T-1) Who am I talking to?

T-1: Us. Site 104 containment staff, Iahel’s followers, sleeping god of Adytum, we are alive. Were. Always have been. Are you still talking?

E11-1: Yes. I am aware you are alive. So, are the consciousnesses of the Site 104 staff contained within you?

T-1: Georgia Lamento, Karey Meyers, Stephan Gold, Travis Mason (The entity continues to list the names of 52 Site 104 staff, the presumed titles of seventeen unknown individuals, “Karcist Iahel”, and a severe verbal sensory hazard)

E11-2: Iahel? He’s the guy who made you, right? Is he still in there?

T-1: He I am alive inside us. We he were speaking. Am you? No, only half Epsilon go away. Run! You’re going going!

E11-4: What is that meant to m-… okay, nevermind. I can only feel one psionic signature in your body. You can’t possibly contain that many people.

T-1: We are one. Mind thinks synchronise. Grow, make hive. Ascend and be one. One great, one man grand. One will be strength, one day one tomorrow!

E11-1: One mind, too. Can you isolate your components, let us talk to someone in particular?

T-1: No no not someone, never separate, we are and will be have been one. Time to go to school! Bye Robert, better luck next time!

E11-3: This is pointless. Shoot it, let’s get on with this.

T-1: Not now! When don’t kill! Will not kill SCP-3391! You came to kill us, you come to kill us, why aren’t you saving me? Holy shit what’s going on?! Help, help, h-

<E11-2 shoots T-1 in the head a total of seven times. Despite suffering extensive cranial damage, the entity remains conscious and alive until the sixth shot.>

E11-2: Tough fucker.

E11-6: Are we equipped to handle this? This is shaping up to be a whole new skip, at the very least. We’ve already lost one of our people, we shouldn’t make that all nine.

E11-1: We’re pressing on. We have to find out what this thing is, and whether we can stop it. We can’t risk further contamination, god forbid a bigger MTF gets taken over by this thing. Blast the pustules. We’re not leaving these things to bite us in the ass later.

<Epsilon-11 shoot the remaining pustules, terminating all entities contained within. A total of seventeen are encountered and subsequently dispatched. Several instances are noted to resemble already terminated staff, or the same ‘base’ individual as another instance.>

E11-2: Now that that’s been dealt with…

<The Task Force continues throughout the facility. Hostile staff are regularly encountered in groups of two to four, usually making incoherent statements directed at Epsilon-11. Notably, some members of staff are encountered several times, even after their confirmed termination. The MTF proceeds to Elevator Shaft F-2, and prepares to descend to the containment level.>

E11-9: Jesus. This place sickens me. All of these people, twisted into monsters by some fucked up anomaly.

E11-6: They don’t talk properly either. Just that senseless babbling.

E11-4: They’re so confused. They feel like children, lashing out at whatever they see. I don’t think it even knows it’s hurting us.

E11-2: This isn’t time for sympathy. The thing’s killing us with our own people. Squad Leader, what’s the holdup?

E11-1: The elevator’s got power, but the lockdown’s jammed the carriage. -5, get the breach materials, we’re rappelling down the shaft.

E11-5: Prepping the breaching charges.

<E11-5 plants an explosive package on the bottom of the elevator.>

E11-5: Clear!

<The charges explode, destroying the floor of the elevator carriage. Epsilon-11 rappel down the elevator cable, landing on the Primary Containment Level, where SCP-3391’s chamber was previously located.>

E11-3: Wow. This place is infested.

E11-4: I can’t even see the walls behind all this meaty crap.

E11-5: Hey, you think there might be survivors down here?

E11-6: I doubt anybody managed to live this long. We must’ve killed at least fifty guys by now. There’s no way anything could’ve avoided those things.

E11-1: It’s our mission and our duty to check. Come on. Maybe we’ll even be able to recontain the threat without having to fry the whole site.

E11-4: Hey, wait. You hear that?

E11-2: No. What?

E11-4: There’s people out there. I… I think they’re on this level. They’re not possessed or controlled like the others. They must be the psychically resistant staff. As you said, -1, it's our mission and our duty to get them out.

E11-1: Right. -2, you take nine and follow -4. The rest of you, come with me. We’re heading deeper into the facility to look for more. The security detail might be locked up in the shelters. You’ve got your assignments, let’s move.

<E11-2, -4 and -9 emerge from the shaft and proceed down the entrance corridor. They follow -4’s lead, which takes them to the site’s main safety bunker. Meanwhile, E11-1, -3, -5, -6 and -7 walk straight forward, toward the original containment wing. At this point Epsilon-11 is split between two groups of 4 under the command of E11-2 and E11-1 respectively.>

<E11-2 arrives at the evacuation shelter and attempts to access the safety bunker. His authorisation is denied due to the site’s lockdown procedures. He knocks on the door.>

E11-2: Hello? Anyone in there?

Unknown 1: <Indistinct>

E11-4: He can't hear us. There’s three people in there, but they’re not in good shape. Our only option might be to cut open the door.

E11-9: We’re entering the bunker, okay? Just stay calm.

<E11-9 uses a thermal cutter to open the door over the course of several minutes. Meanwhile, E11-1 and his portion of the team continue to explore the site.>

E11-3: The site schematics say the security room should be just on our left. We'll want to get a hold of the security camera feeds.

E11-1: Understood. Let’s recover the data.

<The squad open the security room door, revealing a large arthropodic entity, displaying features and anomalous attributes similar to those of SCP-████. The entity attacks Epsilon-11, grabbing and consuming E11-5.>

E11-5: No no no, wai- (Footage indicates that E11-5 perished at this point)

E11-7: Holy shit! Shoot it, shoot it!

E11-3: No, just fucking run! We don’t stand a chance against a copycat skip!

<E11-1, -3, -6 and -7 turn away from the arthropod and flee down the corridor, but are cut off by three individuals with similar appearances to E11-8 and E11-5.>

E11-1: What the hell? B██?

E11-8 Impostor: Sorry, M██████, but it has to be this way. I have to kill three. And then, you have to kill me.

E11-5 Impostor (1): SCP-3391, it’s… hard to describe. It gets in your head, you know? And it already knows what’s we’re going to do. So this has to happen.

<Affected MTF members open fire on Epsilon-11. Despite their outward appearances mimicking MTF armour and equipment, their clothing and weaponry prove to be bonded to their bodies, and formed out of a soft chitin. E11-3 is perforated with shards of bone. Her body quickly swells, and is subsumed by an enormous cancerous growth. The arthropodic entity pauses to spit a caustic substance over the tumour, before consuming the resultant slurry.>

E11-7: Crap, -3! It’s fucking eating her!

E11-1: There’s no time for that, open fire!

E11-5 Impostor (2): Don’t be afraid. If you could see what I can, you’d already know how it all ends.

<E11-1 and E11-7 terminate the impostor MTFs. The arthropodic entity rapidly engorges itself on the remains of E11-3, and swells in size, gaining significant mass and anomalous abilities. It quickly approaches and grabs E11-6. He is lifted into the air and disemboweled, while the entity engorges itself on the spillage. -6 remains conscious and primes several explosives on his person,>

E11-6: You want some? Come and get it, you spindly bastard.

<The entity and -6 are engulfed in a fireball, incinerating both individuals. -1 and -7 are able to avoid the blast and continue running from the security room.>

E11-2: What’s going on over there? I heard explosions. Are you alright?

E11-1: Lost five, six and three. I’m sorry, can’t talk for long.

E11-7: Met some sosies of eight and five, too. Had to shoot them in the head. Again.

E11-4: It took over an entire site, turned its inhabitants into puppets and now it’s turning our own people against us?

E11-1: And I think it’s getting smarter, too. Found six earlier, he talked to me; almost like a person. Said… he had to kill -3. And then, I had to kill him.

E11-9: That doesn’t seem to make much sense.

E11-4: Either way, it’s getting more coherent. Smarter. It took the staff, and it started making fucked up versions of them, and then it took -5 and -8, and started creating its own soldiers.

E11-7: And it made a couple of SCPs to boot.

E11-2: Cut the theorising. The bunker door's cut through, we're opening it now. Hey! We’re coming in!

<While E11-7 and E11-1 mute their comms, E11-2, -4 and -9 enter the bunker. It is entirely free of the tissue seen outside. Three members of Site 104 staff are present inside. Two are on the other side of the chamber, one of whom is armed with a pistol. An additional member of staff is standing to the side, hyperventilating.>

Admin Staff Remer: Stop! Don’t take another step, I’ll shoot!

E11-2: Put the gun down! This is Epsilon-11, we’re here to get you out of the facility.

Guest Researcher Esther: They’re more fucking mimics, John! Get the hell away from us!

E11-4: Look, if you’re not going to cooperate we’ll leave you here; but right now, we’re the only chance you have of getting out.

<After several seconds, Remer looks at Esther, puts down his gun, and steps forward.>

Remer: Fine. Lead the way, then.

E11-9: Hey, uhh, are you okay over there? (Gesturing at the third member of staff)

Security Officer Tamry: Yeah, yeah. Just go on ahead. I’ll be right behind you.

Esther: How’re we going to get out? The containment level’s been locked down.

E11-4: We’ll be escorting you to the elevator. We have rappel lines there. -2, how far do we have to go?

E11-2: Ten minutes’ walk, by my count. Come on, let’s go.

Tamry: About time, too.

<The rescue team collect all three staff, and begin escorting them to the elevator. Meanwhile, E11-1 and -9 converse quietly in the security wing of the containment level, apparently avoiding the arthropodic entity.>

E11-9: What’s the plan now?

E11-1: The mission’s a bust. The best we can do is make sure the others get to the surface safely, and maybe get ourselves out too; though I don’t really see that happening now.

<E11-1 begins transmitting to E11-2 at this point>

E11-1: Hey, are the staff out safely?

E11-2: Yes, we’re proceeding to the elevator now. What’s your status?

E11-1: We’re holed up in the security wing, pursued by a large cryptid. No way we can beat it, and no way we can get out while it’s blocking the corridors.

E11-2: Do you need assistance?

E11-1: No. I was just making sure you were safe. You should get going.

E11-2: You don't need to micromanage us. Shouldn’t you be a little more preoccupied with keeping yourself alive?

E11-1: There's no chance in hell me and -7 are getting out of this. Keep the men safe, yeah?

E11-2: I will, sir.

E11-7: Shit, I hear something coming, get down!

<E11-1 muted his communications at this point, before following E11-7 behind a crate. An unknown number of humanoids enter the room, and immediately attack the two agents, resulting in a prolonged firefight. Meanwhile, E11-2 and his segment of the task force traverse the facility.>

E11-9: I know we should save it for the debriefing, but what exactly happened down here? This place looks totally grown over.

Tamry: I- I don't know. God, half the staff just started grabbing at their chests, yelling for medical. Next thing we know we’re outnumbered, fighting our own people, and… I know it’s what we’re trained for but it just felt so terrifying.

E11-2: It’s perfectly normal to be scared. Nobody expects you to deal with something like that. What matters right now is that we get back to the surface. You don't have to worry about a thing.

Remer: You haven’t got anyone else coming down here, right? No more teams or anything?

E11-2: No, we’re the first responders. Command’s on overwatch. If anything happens to us, they’ll send in a specialised bioteam, smoke the place out.

Esther: Have you got them on the radio?

E11-9: No. The facility's too far underground for us to get a signal. Why do you ask?

Tamry: Oh, you know. Getting to know you is all.

<Esther and Tamry attack and restrain E11-4, displaying anomalous physical strength. While Remer assaults E11-2 and -9, Tamry shatters -4’s helmet, and places a hand over her face, causing her body to rapidly calcify. Shortly afterward, Tamry begins consuming her.>

E11-9: What the fuck!? K███ said they were safe!

<E11-9 throws an incendiary device at the apparently affected staff, incinerating Remer and Esther. Tamry, however, leaps onto E11-9, and begins caving in his helmet. The staff member is terminated through a shot to the back of the head before they can kill -9.>

E11-2: Yeah. She did. She couldn’t have gotten it wrong she’s- she’s never been wrong before.

E11-9: This fucking thing can copy our psionic signatures? Our gear? The fucking skips inside the facility?! Fuck this noise, I’m heading to the surface. We’re getting out of here!

<E11-2 and E11-9 run through the facility toward the elevator. Upon reaching it however, they discover that it has been entirely overgrown by cardiac tissue.>

E11-9: Shit, shit shit!

<E11-9 collapses against a wall.>

E11-9: We’re going to die down here! We’re actually going to fucking die!

E11-2: It’s too smart. It knew everything about us. It led us into a trap, got what it needed from us. The gibberish, the staff, the skips… it’s been playing us this whole time.

E11-9: Who cares?! We’re boned, none of this matters anymore! Can’t even get a signal up to command. All we can do is sit here and wait like a bunch of impotent fucks!

E11-2: Shut up! We still have a chance to get out of here. We’ll reach -1 and -7, they’ll know what happens next.

E11-9: And then what? Even if they’re alive, what can they do?

E11-2: We’ll blow this place up. Activate the on-site nuke, it's the only option left.

<E11-9 makes radio connection with -1.>

E11-9: Squad leader! What’s going on over there?

E11-1: We’re bogged down! Dozens of staff, and more copies of our team.

E11-2: Copy that. The exits are sealed off, we’re on our way. Stay alive.

<E11-1 and E11-7 notice a group of MTF soldiers entering the room. Their facial features cannot be seen behind their visors.>

E11-7: More of them! Shit!

<-1 and -7 exchange fire with the entities to little effect. -7 is shot in the chest and begins to disgorge large quantities of blood and flesh from his mouth. He rapidly succumbs to blood loss and collapses. -1 crouches behind a crate, no longer engaging the hostile MTF.>

E11-1: They've got O█████. I'm sorry, but I think I'm going to die.

<Several anomalous humanoids emerge from the walls, with a lack of facial features and identifying traits. They do not acknowledge E11-1, instead standing in place. All present copycat MTFs also stand still and do not approach -1.>

E11-1: (Whispering) They've stopped. Something's happening.

<All anomalous humanoids within the facility suddenly take on the appearance of E11-4, including her armour and equipment. All instances of E11-4 begin speaking, but fail to notice E11-1.>

E11-4: Hello? Is anyone there?

E11-9: What the hell? Squad leader, is -4 over there with you?

E11-4: It's so dark… is anyone out there? My name is K███. I'm here to help.

E11-1: Shit, this can’t be happening… -4, you’re dead too?

E11-4: Hello? I’m- are you there W███? M██████? Someone answer me! Wait… who- who are you?

E11-2: She can’t hear us. I think she’s talking to the gestalt. Her psionic training must be keeping her independent.

E11-4: But… why? They weren’t in your way. You don’t need to kill them, you didn’t need to hurt us!

<E11-4’s faculties degrade significantly, causing her to lose consciousness for several seconds. When she begins talking again, her voice is slow and slurred.>

E11-4: Shut up! I- is that you? Wait, M██████? Why’s he down there?! What are you doing?!

<-4’s speech degrades further, rendering her communications nearly incoherent>

E11-1: Shit, she must be going. No no no, don’t go now, K███, stay in there!

E11-4: No, you get the fuck away from him! You mindless freak, you’re not killing anyone else! Look into my head! That's the world I'm fighting for. You’re not going to hurt one more person, you hear me?! I’ll make sure of that.

<E11-2 stops broadcasting entirely. All anomalous humanoids collapse, and cease lifesigns. E11-2 and -9 reach Squad Leader’s position.>

E11-1: Fuck. She’s gone. I’m sorry, I… she, and everyone else are dead, because of my stupid decisions.

E11-2: Wasn’t your fault. None of us could’ve known what was down here. It’s good to see you again, sir.

E11-9: But more important than sappy shit is our plan of action. What do we do now? There’s no way we’re getting out of here, that’s for sure.

E11-1: This abomination’s never getting out of here. We’re arming the nuke. I don’t care how far it’s spread, it’s not outrunning a twenty kiloton bomb. If you still want to get out, do it now. I won’t make you stay.

E11-9: Heh. There’s no chance in high hell we can get out. We’ll have to trust command to wipe out the stragglers.

E11-1: Come on. The nuke room’s not too far from here.

<The remains of Epsilon-11 traverse the facility. They encounter several anomalous organisms, all of which are only nominally aggressive, fleeing after only minimal fire. Several fail to acknowledge the team altogether. E11-1, -2 and -9 stop outside of the Site 104 security control room. Epsilon-11 is reunited at this point.>

E11-1: Come on. Let’s finish this.

<E11-1, -2 and -9 enter the security room elevator, and descend to the warhead housing chamber.>

E11-1: We’re here. This is it, I guess. The day we die.

<MTF Epsilon-11 walk to the back of the chamber, and activate the site nuclear terminal.>

E11-2: The remote broadcast beacon’s still functional. Setting up the link.

<Epsilon-11 make contact with surface Command through the Site 104 emergency beacon.>

E11-1: Command, are you reading us? This is MTF Epsilon-11, reporting from Site 104 control.

Command: We’re reading you.

E11-1: Command this is Squad Leader, we’re scuttling Site 104 on suspected Keter breach. I’m detonating the Alpha Warhead now. It’s the only way to be sure.

E11-9: From day one, we got taught to put our faith in our intuition; and right now, I believe more than anything else in the world that this monster has to die.

Command: We understand. You have the go-ahead, Epsilon.

<E11-1 activates the on-site nuke on a 30 second timer.>

E11-2: We’re uploading our data now. Running it through the transmitter.

E11-9: Tell my family I love them, yeah?

Command: We will. Godspeed, everyone.

E11-2: Don’t send anyone down here. Fence it off, salt the earth, whatever it takes to keep this under control. Never let it get to the surface.

E11-9: The nuke might not even kill the damn thing. But it’s the best we can do.

E11-1: Five seconds, everyone. It was an honour to serve.

<The Site 104 nuclear warhead detonates, destroying the entire complex. The underground and surface installations are vaporized instantaneously, including all anomalies. The former site is subsequently fenced off and designated a radiation and biohazard restricted area. An extremely powerful wave of Akiva radiation and psionic energy is released by SCP-3391-3 shortly before its immolation, with as of yet unknown effects.>