Object Class: Euclid
Special Containment Procedures: The area affected by SCP-830-JP is to be blocked and patrolled by 5 security personnel - a cover story about wild bears has been recommended. Any trespassers are to be immediately detained, questioned, and administered Class A amnestic. At 20:00 on 08/30 every year, Security personnel are to speedily withdraw from the affected area. When SCP-830-JP manifested, it is to be observed via stationary security cameras on the top of Mt. ████, a neighboring mountain of Mt. ███████; direct observation of SCP-830-JP is never allowed.
As soon as the manifestation of SCP-830-JP is confirmed, an autopilot strategic bomber is to take off in the guise of normal aircraft and start bombing SCP-830-JP by incendiary bombs. Fireworks displays are to be held throughout surrounding area, under the cover stories of "Village revitalization campaign" and "Remembrance festival in memory of the fall of ███████ Castle". After the protocol execution, the surrounding areas are to be monitored to ensure that the local citizen didn't notice the anomalous phenomenon. If someone notices the anomaly, use of Class A amnestic is approved.
Description: SCP-830-JP is a structure with the appearance of a Japanese castle of the Azuchi–Momoyama period that manifests on the top of Mt. ███████ of ████████ Prefecture, Japan. SCP-830-JP only materializes from 21:00 on 08/30 to 03:00 on 08/311 every year.
The current area of SCP-830-JP is approximately 150,000m2 and it consists of various kuruwa (including honmaru with a height of 55m, ninomaru and sannomaru), watchtowers and fortifications. Due to its current expanded armaments, it is believed that it is extremely difficult to bring down by the frontal attack using the arms of Azuchi-Momoyama era. Many banners have been discovered in various places of SCP-830-JP; and all banners are decorated with emblems, which have been identified as that of warlords who had served to the ██████ Family.
Upon the manifestation of SCP-830-JP, any other objects in the area temporary disappear. In the past, the Foundation installed the explosives beforehand to blow up SCP-830-JP - this plan failed when the explosives vanished by above-mentioned phenomenon. Disappeared objects will be re-appear when SCP-830-JP de-manifests.
████ instances of humanoid entity wearing the armor of Azuchi-Momoyama era (referred to as SCP-830-JP-1) exist in SCP-830-JP. SCP-830-JP-1 instances are armed with the common weapons for Azuchi-Momoyama era (katana, bow and arrows, matchlock, etc) and extremely hostile against any people approaching SCP-830-JP. SCP-830-JP-1 instances do not display abnormal physical resistance and can be killed like normal human by fatal wounds. Furthermore, the commander of SCP-830-JP-1 instances always can be found somewhere in the honmaru. If the commander instance is neutralized or ██% of SCP-830-JP is destroyed, SCP-830-JP will "fall" and de-manifest early.
Upon the de-materialization, individuals who are inside SCP-830-JP appear in the anomaly's manifestation area in the state of unconscious. All attempts for recording the de-materialization from the inside of SCP-830-JP ended in failure due to the malfunction of recording devices by unknown causes.
If a sapient individual makes direct visual contact with SCP-830-JP, they will be compelled to seek out any available tools and use those tools as weapons to attack SCP-830-JP; Class A amnestic or the de-materialization of SCP-830-JP can neutralize this effect. Usually, affected civilian are killed by SCP-830-JP instances at the main gate. Once killed, victims vanish immediately - and manifest as SCP-830-JP-1 instances the following years.
If SCP-830-JP has not "fallen" when it demanifests, following manifestations will experience a slight size increase. Documents recovered from Shūshū-In have shown that SCP-830-JP was expanded ██ times in total to date.
SCP-830-JP was handed over from Shūshū-In in 18██. Recovered documents state that this anomaly is originated from the grudge of ████████ Kitabatake, the lord of ███████ Castle and one of the vassals of ██████ Family. In 15██, despite Kitabatake's adoption of a defensive strategy, his castle fell in one night by a novel tactic of ███'s army. According to further details, its current anomalous property first occurred in 1615, at the point ███████ Castle was abolished by the Ikkoku Ichijo Rei2. Before this, SCP-830-JP had been manifested as phantom samurais in ███████ Castle.
Initially, subjugation and exploration had been tasked to multiple Foundation mobile task forces.
In 19██, shortly after Foundation Manufacturing Department developed the high-powered incendiary bomb to contain SCP-███-JP, Dr. ████ proposed its diversion to the containment of SCP-830-JP, by combining autopilot bombers provided from U.S. Military. In following year, Dr. ████'s proposal was put into action and SCP-830-JP "fell" without any problem. Thereafter, current Special Containment Procedures were established.
Addendum: 20██/8/30, ██ years after the establishment of Special Containment Procedures, a wooden sign materialized in the SCP-830-JP area after the bombing.
S T O P
Next year of this incident, usual containment protocol was executed and no further anomalous deviation was observed. Thus, Special Containment Procedures have not been updated.