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Item #: SCP-4064
Object Class: Euclid
Special Containment Procedures: A fenced and guarded perimeter is to be established three (3) kilometers out around the town of ██████, WV. All acknowledgements of ██████’s existence are to be removed from public records, and roads are to closed as needed to minimize the chances of civilians discovering ██████. All individuals other than SCP-4064-1 found within the containment zone are to be administered class-a amnestics and taken out of the containment zone, and any found recording devices are to be destroyed.
All instances of SCP-4064-1 not being used for testing or research are to remain within the containment zone. SCP-4064-1 are not to be allowed access to recording devices or microphones, unless explicitly approved for testing.
All personnel assigned to SCP-4064 are to wear hearing protection whenever they are at risk of hearing SCP-4064. MTF Epsilon-5, which consists of ██ SCP-4064-1 instances trained for use by the foundation against threats related to SCP-4064, is to be on standby at all times, in case of a breach involving SCP-4064.
Due to risk of a GH-Class event, any research involving the recording of SCP-4064 requires approval from Head Researcher Webster.
Description: SCP-4064 is an obscure, highly cognitohazardous dialect of English. As of writing, there are believed to be ████ speakers of SCP-4064, which are collectively designated SCP-4064-1. SCP-4064-1 are able to converse in SCP-4064 with other SCP-4064-1 instances without cognitohazards manifesting. However, when sentient beings other than SCP-4064-1 hear SCP-4064 spoken aloud, they experience a wide spectrum of physical effects, depending on what is said. These effects manifest whether or not the effected individual recognizes SCP-4064 as language. These effects only manifest when SCP-4064 is spoken aloud; if written, it can be read normally1.
Adults not raised speaking SCP-4064 are incapable of learning it, due to the inherent danger of hearing it spoken. Children born to SCP-4064-1, who are raised in an environment where SCP-4064 is predominantly spoken appear immune to the cognitiohazards, with the exception of [DATA EXPUNGED]. As such, children born in ██████, WV are to be raised by SCP-4064-1, and if possible, their parents.
SCP-4064 is believed to have originated in ████████ county, West Virginia. The community of ██████, WV, has been isolated from general society since ████, and it is believed SCP-4064 developed as a result of this isolation, although the exact way in which the dialect developed is not known, and is the focus of ongoing research by foundation cognitolinguists.
Addendum 4064-A: Testing Log
SCP-4064-1 were given a number of prompts for speaking, and was recorded. Recordings were played back to D-Class personnel, and effects were logged. Select entries are listed below.
| Prompt | SCP-4064-1 Response | Effect on Listener |
| Give a friendly greeting. | “howdy friend, how’s yer day gon’on?” | Upon hearing recording, D-186 experienced a drop in internal temperature of about 16K. Effect persisted, and D-186 died of hypothermia. |
| Give a friendly farewell. | “See y’soon, friend.” | Upon hearing recording, D-187 appears unnaffected. However, three (3) days after testing, they experienced a pulmonary embolism and expired, resultant from a deep vein thrombosis, believed to have developed as a result of hearing SCP-4064. |
| Give an expression of gradtitude. | “I’d jus’ like to say, thank ya.” | Upon hearing recording D-189 is degloved, by a sudden force pushing their body backwards, but not doing so to their epidermis or dermis. D-189 expired from their wounds while in the site ██ clinic. |
| Say the first word that comes into your head. | “Umm.. Table.” | Upon bearing recording D-192 experiences epistaxis, which resolves it within four (4) minutes. Note: It seems that even single words can have an effect, although it may be less severe than entire phrases. |
| Say the word “Hello”. | “Hello.” | Upon hearing recording, D-193 Immediately loses consciousness. They are able to be awoken by staff. Note: this suggests that the cognitohazard may be a result of the accent, not the vocabulary. Further testing needed. |
| Say the Word “Hello”. | “Hello.” | Upon hearing recording D-194 loses consciousness, as happened in the previous test. Note: This shows that cognitohazards are not random, and are explicitly related to specific phrases. |
| Recite the following phrase: “The quick brown fox jumps over the lazy dog.” | “The quick brahn fox jum’s o’er the lazy dog.” | Upon hearing recording D-194 begins expressing extreme distress and coughing violently, before quickly expiring. Autopsy reveals large quantities of coarse sand in D-194’s pleural cavity. Note: This further suggests that vocabulary is unimportant. |
| Sing the song “Camptown Racers”. | [DATA EXPUNGED] | [DATA EXPUNGED] Note: Further tests involving singing are forbidden. |
Addendum 4064-B: Breach of Containment
On ██/██/██, during testing of SCP-4064 at Site ██, multiple Euclid and Keter class anomalies breached containment. During the breach, three SCP-4064-1, who were in the process of recording examples of SCP-4064 for testing, were evacuated, after receiving explicit order not to speak. However, while in the process of evacuation, one of the SCP-4064-1 instances was wounded by gunfire, and began crying out in pain. This resulted in two (2) casualties, and the wounded SCP-4064-1 instance was terminated. The remaining instances were angered by this, and began hurling profanities and outrage at personnel, resulting in fourteen (14) casualties, before the instances escaped foundation custody.
The escaped SCP-4064-1 instances were located after four (4) hours outside containment, but upon being confronted by MTF Epsilon-5, they began singing what is believed to be a folk song from ██████. While the MTF was unaffected, personnel in the Site ██ control center were affected, due to an apparent failure to mute audio from the MTF’s microphones; affected personnel began [DATA EXPUNGED] resulting in a further sixty-three (63) casualties, before the two (2) SCP-4064-1 instances were terminated.
