Item #: SCP-XXXX

Object class: Euclid

Special containment procedures: SCP-XXXX-1 and SCP-XXXX-2 are to be held in a 10m×5m×5m chamber with soundproof steel walls at least 45 cm thick. Both SCP-XXXX-1 and SCP-XXXX-2 must each be cuffed to a bed by the arms, legs, and neck, with their heads tilted and immobilized as to be constantly staring at each other. For humanitarian purposes and prevention of [DATA EXPUNGED], SCP-XXXX-2 must be kept in a medically-induced coma. Both individuals must be fed intravenously.

In case of SCP-XXXX-2 expiring or becoming SCP-XXXX-1 by its predecessor expiring, the surrounding area must be evacuated and a D-class personnel must be inmediately designed as the new SCP-XXXX-2, and the above containment procedures must be applied. In case of a security breach during the replacement of SCP-XXXX-2, all personnel must be evacuated from Site except for a D-class personnel, the to-be SCP-XXXX-2. Site will then be sealed, until SCP-XXXX-1 is under control. If no D-class personnel is available, any personnel will suffice.

Description: SCP-XXXX is a condition of unknown nature that affects one human being at a time, known as SCP-XXXX-1. When becoming SCP-XXXX-1, the subject will begin to scream at a power between 110 and 130 decibels. In its hunt state, the power of the scream has been observed to reach 2██ decibels. SCP-XXXX-1's scream will not stop, not even to breathe, until subject expires. When this happens, the last alive person to have been seen by SCP-XXXX-1 (known as SCP-XXXX-2) will begin to scream, and become the next instance of SCP-XXXX-1.

SCP-XXXX-1 appears to be in a constant state of extreme pain, which is believed to be the cause of the scream, although it does not explain the unceasing nature it. SCP-XXXX-1's needs are not altered by the condition, save sleeping and blinking, which SCP-XXXX-1 has never been observed to do. Of note is that SCP-XXXX-1 does breathe, though the means through which it does so are currently unknown. The constant screaming state of SCP-XXXX-1 implies that for it to breathe, both inhalement and exhalement of air should occur simulteneously, which, while possible to achieve, requires training which SCP-XXXX-1 usually lacks.

Should SCP-XXXX-1's life be compromised while there is no SCP-XXXX-2 (see Experiment Log XXXXa-03), SCP-XXXX-1 will enter its hunt state. SCP-XXXX-1 will become increasingly agitated, and will attempt to break free of any restraints, subsequently beginning a chase for a suitable candidate for carrying the condition. To this point, no material has proven effective in stopping SCP-XXXX-1's advance, as its strength will steadily increase until it finds a suitable candidate, but stronger materials will delay the breakthrough and allow more time for security measures to be implemented. This implies that, during this state, SCP-XXXX-1 may not be killed, and so the existence of a suitable candidate must be immediately assured.

Addendum XXXXa: A series of tests to get more information on the effects of SCP-XXXX on individuals of specific characteristics has been realized. In each experiment, SCP-XXXX-1 was attempted to be terminated by projectile bombardment, and the results noted.

Experiment Log XXXXa-03
Date: ██/██/198█
SCP-XXXX-1 is a caucasian male, aged 16 hours, son of D-3642. No SCP-XXXX-2 has been selected. SCP-XXXX-1 was carefully given birth in a way it had not seen another human being, save the previous instance of SCP-XXXX-1, which had been terminated upon contact with the infant.
Results: Injuries suffered by SCP-XXXX-1 should have killed it inmediately, as it had received multiple shots to the brain, and its left lung along with most of its digestive system had been shot off its body. The eyes were notably uninjured. Despite mantaining these substantial injuries, SCP-XXXX-1 was not killed in the termination attempt, which resulted in an augmentation of the subject's screams' to 170 decibels, and an increase in movement and agitation. Subject appeared to be trying to free itself from its restrains. After 3 minutes of attempting escape, SCP-XXXX-1 managed to tear its body at the stomach level, and the upper part (which was the only one to mantain activity, as the lower part of SCP-XXXX-1's body appeared to expire inmediately after the separation) propulsed itself by the mean of what was left to its arms towards the containment cell's wall, which it managed to break through in 10 seconds. SCP-XXXX-1 ceased all activity when it reached Agent ███████, who was stationed outside the chamber, and who inmediately became SCP-XXXX-1 after the newborn expired.

Experiment Log XXXXa-05
Date: ██/██/199█
SCP-XXXX-1 is a 23 years old caucasian female, born blind. D-4424 was placed in the chamber on the bed corresponding to SCP-XXXX-2.
Results: Following the attempted termination, SCP-XXXX-1's scream augmented to 186 decibels. Subject also appeared to be experiencing even greater pain than the usual. 10 seconds after SCP-XXXX-1 entered its hunt state, its eyes appeared to gain vision. Subject inmediately saw D-4424 and proceeded to expire, resulting in the usual becoming of D-4424 into SCP-XXXX-1.
Notes: Research into a possible cure of blindness denied, as to this point every instance of SCP-XXXX-1 has mantained it until its time of death.

Experiment Log XXXXa-06
Date: ██/██/199█
SCP-XXXX-1 is a 54 years old male of native american descent, who by a medical condition was born without eyes. D-236 was placed in the chamber, on the bed corresponding to SCP-XXXX-2.
Results: Following the attempted termination, SCP-XXXX-1's scream reached 2██ decibels, even higher than in Experiment XXXXa-05 . The resulting shockwave resulted in D-236 spontaneously bleeding from its eyes, ears, nose and lips. 15 seconds after SCP-XXXX-1 entered its hunt state, [DATA EXPUNGED].

Request to try to send SCP-XXXX-1 into space by Dr. █████ denied.
We know that SCP-096 caused a plane to crash. Why do you expect this one to be different? Sending into space would be a great expense of ressources, and it would teach us nothing.