+ The Abyssal Choir
+++ **Object Class:** **//Keter//**
++++ **Special Containment Procedures:**
Due to the remoteness and depth of SCP-8165, direct containment is unfeasible. A cordon of deep-sea monitoring stations, disguised as geological research facilities (designated Delta-34), has been established in the vicinity of the Mariana Trench. These stations are equipped with advanced sonar systems and non-lethal deterrent devices designed to misdirect SCP-8165 entities. Any unauthorized vessels or expeditions near the site are to be intercepted under the guise of maritime safety enforcement.
In the event of SCP-8165 initiating a large-scale “//Call Event//” (designated Call-1 through Call-N), Protocol //Triton-X// must be enacted: all naval assets in the Pacific are to focus on misdirecting and neutralizing summoned leviathans while maintaining strict secrecy. The public dissemination of information regarding SCP-8165 is prohibited under Executive Order ████-1962, with all witnesses to be amnesticized.
+++ **Description:**
SCP-8165 refers to a seemingly ancient civilization of sentient humanoid deep-sea creatures residing within a sprawling, bioluminescent abyssal city complex (designated //Site-X//), located approximately 11 kilometers beneath the ocean surface in the Mariana Trench. It occupies an area about have the size of the state of New York.
++++ **Physiology**:
SCP-8165 entities (collectively referred to as the “//Abyssal Choir//”) are humanoid in shape, though their appearance diverges significantly from terrestrial biology.
* Body Structure: Their bodies are elongated and spindly, measuring between 3–4 meters in height. Limbs end in multi-jointed digits resembling prehensile tendrils.
* Skin and Flesh: Translucent, jelly-like flesh reveals internal organs that emit a faint luminescent glow, likely functioning as a form of communication or camouflage.
* Photophores: A bioluminescent “crown” of photophores encircles their heads, pulsating in complex patterns during vocalizations.
* Pressure Adaptation: Their physiology allows them to withstand immense pressures. Internal anatomy includes crystalline cartilage structures and hemolymph-like circulatory systems, suggesting evolutionary divergence from all known terrestrial life.
Autopsies of deceased SCP-8165 entities recovered during Call Events reveal structures resembling neural filaments extending through their appendages, indicating a distributed intelligence network. This may contribute to their ability to coordinate “//Calls//” with near-perfect precision.
++++ **//The City// aka //Site-X//:**
Site-X is a massive sub surface city complex sprawled across multiple tiers of the Mariana Trench’s Challenger Deep. The city appears to incorporate natural geological formations into its architecture, with bioluminescent fungal growths and crystalline spires forming its skyline.
Data points to the city extending in a subterranean fashion far below the ocean floor. The visible “skyline” seems to simply be the uppermost levels.
++++ **Key features of Site-X include:**
* The Abyssal Spires: Towering 1-2 kilometer tall, coral-like structures emitting rhythmic pulses of light, believed to amplify SCP-8165’s vocalizations for long-range communication.
* The Cathedral: A 4-kilometer-wide, dome-like structure embedded into the trench wall emitting musical tones. Initial scans suggest this site functions as both a cultural and ritualistic hub. Murals carved into the structure depict SCP-8165 entities worshiping SCP-8165-A leviathans, suggesting a symbiotic or deific relationship. The structure seemed to be a combination of building materials including stone, crystal and organic in nature.
* Bio-Forges: Organic foundries constructed from chitinous material, where SCP-8165 produces tools and artifacts. These include bioluminescent weapons, pressure-resistant armor, and sonic devices capable of disrupting sonar systems.
* Bio-Craft: SCP-8165 entities have been recorded entering “bio-craft” in conjunction with calls. Organic “craft” constructed from both chitinous and metallic material, have been witnessed exiting the city and rising to and out of the surface of the ocean.
These bio-craft are pyramidal or rhomboid in shape but always with a point of the shape pointing downward.
These craft move in excess of 14,000 km/hour and cannot be tracked on radar. It is theorized they may be traveling off-planet as they frequently ascend directly up into the sky at incredible speed. They range in size from 8-60 meters in size.
Subsurface readings indicate that Site-X predates recorded human history by many thousands of years, with some sections estimated to be hundreds of thousands of years old. Evidence suggests Site-X was constructed to weather catastrophic environmental shifts, possibly linked to SCP-8165-A instances.
++++ **Discovery and U.S. Coverup:**
In 1962, the U.S. Navy initiated a classified operation to investigate unexplained sonar anomalies detected in the Mariana Trench. The project, code-named Operation Deep Siren, deployed the bathyscaphe Trieste II to extreme depths. While conducting surveys, the team encountered a glowing structure resembling the Abyssal Spires and recorded the first audio-visual evidence of SCP-8165 entities.
Shortly after the initial discovery, SCP-8165 entities triggered Call-1, summoning an SCP-8165-A instance later designated “//Leviathan Prime.//” This organism, a massive squid-like creature, caused severe damage to nearby naval assets, including the destruction of the submarine USS Halibut. Survivors described hearing “eerie, harmonious wailing” as the creature surfaced and attacked.
To prevent mass hysteria, the U.S. government classified all findings under Executive Order ████-1962. All personnel involved in the discovery were subjected to amnestic treatment, and research into the Mariana Trench was strictly limited. A narrative of “deep-sea volcanic activity” was disseminated to explain the anomalies.
+++ Addendum - Notable Call Events:
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++++ Incident Report Call-1 (1962):
+++++ Date: March 3, 1962
Following sonar scans conducted near the Cathedral during Operation Deep Siren, SCP-8165 triggered its first documented Call Event. Approximately three hours after the scans began, an SCP-8165-A instance, later designated “Leviathan Prime,” emerged from the trench.
+++++ Description of Leviathan Prime:
* Species Analogy: Cephalopod-like organism
* Length: Estimated at 79.8 meters/262 feet
* Unique Features: Tentacle-mounted photophores capable of emitting concentrated bioelectric bursts, disabling electrical systems in nearby vessels
* Event Details:
Leviathan Prime attacked several naval assets, including the USS Halibut, which was destroyed after sustaining catastrophic hull damage. Survivors reported the sound of “haunting, harmonious wailing” that seemed to emanate from both the leviathan and SCP-8165 entities.
Attempts to neutralize Leviathan Prime with depth charges and torpedoes failed due to its advanced agility and ability to generate electrical countermeasures. The leviathan eventually retreated after SCP-8165 entities performed a synchronized vocalization sequence, suggesting the event was an intentional display of power.
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++++ Incident Report Call-2 (1989):
+++++ Date: August 14, 1989
A private deep-sea exploration vessel, the Nautilus Horizon, transmitted footage of SCP-8165 entities near the Abyssal Spires before losing contact. Hours later, an SCP-8165-A instance, designated “//Leviathan A2//,” surfaced near Guam.
+++++ Description of Leviathan A2:
* Species Analogy: Anglerfish-like organism
* Length: Over 94 meters/313 feet
* Unique Features: A massive
bioluminescent lure emitting hypnotic light patterns capable of causing severe disorientation and hallucinations in human observers
* Event Details:
Leviathan A2 surfaced near civilian vessels and engaged a U.S. Navy task force dispatched to intercept it. The creature demonstrated predatory behavior, using its lure to confuse and incapacitate personnel before dragging the USS Independence beneath the surface.
The leviathan was eventually neutralized using experimental depth charges, though SCP-8165 entities were later observed scavenging the wreckage. Analysis of SCP-8165 vocalizations following Call-2 indicated increased hostility, likely in response to the destruction of one of their summoned leviathans.
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+++ Incident Report Call-3 (2012):
++++ Date: May 12, 2012
After the detonation of a seismic charge near Site-X by the USS Triumph during a classified research mission, SCP-8165 triggered Call-3. Six hours later, seismic sensors detected rapid movement within the trench, corresponding to the emergence of SCP-8165-A3. The emerging entity referred to as //Leviathan A3// was far more massive than those previously encountered.
++++ Description of Leviathan A3:
* Species Analogy: Hybrid Baleen Whale/Mosasaur like organism
* Length: Approximately 442 meters/1442 feet
* Unique Features: Thick, armored hide resembling scaled chitin; bioluminescent markings; maw lined with keratinous baleen plates interspersed with serrated teeth; serrated dorsal fins, and the ability to emit infrasonic growls causing nausea, vertigo, and hallucinations in nearby personnel. Appeared to have three variably sized glowing eyes arranged in a triangle on opposite sides of the head for a total of six eyes.
* Event Details:
SCP-8165-A3 targeted a U.S. Navy task group stationed 70 kilometers from Site-X. This included the USS Nevada, USS Triumph, and USS Seawolf. Initially, it used its immense size and strength to ram the vessels. Reports from surviving crew described coordinated attacks, including tail slams generating shockwaves mimicking depth charge detonations.
SCP-8165-A3 displayed strategic behavior, targeting the USS Nevada first by ramming it from below, resulting in immediate catastrophic failure and the loss of all 139 crew members.
The creature used its tail to create powerful currents, disrupting torpedoes and depth charges launched by the remaining submarines. It also utilized its bioluminescent patterns to disorient crews, flooding control rooms with “eerie, strobing light.”
Reinforcements, including the USS Louisiana and USS Wyoming, arrived after four hours and engaged the leviathan with experimental torpedoes. After sustaining severe injuries to its dorsal fins and abdomen, SCP-8165-A3 retreated to Site-X. Reconnaissance drones later observed SCP-8165 entities tending to its wounds, confirming the symbiotic relationship between SCP-8165 and its leviathans.
Post-incident analysis revealed SCP-8165 vocal activity spiked by 46% in the weeks following the attack, interpreted as either a mourning or retaliatory ritual.
++++ Closing Notes:
The escalating hostility of SCP-8165 and the increasing size and complexity of summoned leviathans highlight the growing threat to maritime security and global stability. Foundation researchers are prioritizing efforts to understand SCP-8165’s culture, communication methods, and possible vulnerabilities to mitigate future Call Events.
End of File.