Addendum SCP-XXXX.1: Incident SCP-XXXX-B-1
On 12/13/1985, two Class-D personnel were sent to SCP-XXXX so the foundation could study SCP-XXXX's anomalous properties. D-120 was given a radio to inform staff of the events that may occur during their exposure to SCP-XXXX. After 1 hour, both D-120 and D-054 entered the cave and fell under SCP-4405's compulsive effect, connection was lost after D-120 proceeds to bury himself in gold upon reaching the interior of SCP-XXXX. Approximately six hours into the experiment, loud roaring resonated from SCP-XXXX. Followed by the emergence of an instance of SCP-XXXX-A which was presumed to be D-120 with massive puncture wounds in its throat and head, and the membrane of its wings were shredded and crumpled. The entity staggered 30 meters from the entrance of the cave before collapsing to the ground and expiring from blood loss and extensive physical trauma. Mobile task forces were sent to the area surrounding SCP-XXXX to investigate.
Only five minutes after they were dispatched, and the first instance of SCP-XXXX-B (formerly D-054) rushed from the cave, reports from surviving personnel claim that the specimens' forelimbs and snout being covered in blood and tissue from the instance of SCP-XXXX-A. The SCP-XXXX-B paused momentarily to survey it's current location, before turning its attention to the deceased SCP-XXXX-A and violently consumed the entity. Personnel was ordered to approach SCP-XXXX-B when the entity took notice of the task force. The creature immediately attacked the site personnel, killing the entire squad while only sustaining a few superficial injuries. The creature took flight and attempted to breach containment, but became preoccupied in destroying the guard towers and facilities within Site-██ with its fire breath, resulting in ███ staff deaths and 432 injuries. During this, it boasted repeatedly of its destructive prowess, identifying itself as "Níðhöggr, Lord of Dragons". SCP-XXXX-B continued its attack for two hours before being successfully shot down by Agent ██████ who managed to fire a rocket launcher from a helicopter into SCP-XXXX-B's left shoulder, severely damaging its wing. The entity was subsequently terminated via concussive missile artillery, but not before exclaiming to surviving foundation staff.
SCP-XXXX-B: You wretched, short-sighted, covetous, mammalian scum! You cannot prevent what has been foretold-(coughs and wheezes)-We all know mankind's dominion over this world is coming to an end! You may have beaten me now, but I will see you all in Hellheim yet… (SCP-XXXX-B collapses into a seizure and foams blood from its jaws for 7 minutes before expiring)
The body of SCP-XXXX-B was taken to Armed Bio-Containment Area-14 for dissection and genetic testing despite of the extensive damage sustained to the corpse. Other SCPs that breached containment during the incident were eventually contained with no further casualties. SCP-XXXX-A entities resumed their normal behavior the following day when questioned of the events that transpired, many of which claimed to be unaware the entity's existence and became abnormally distressed when questioned further.
Addendum SCP-XXXX.4: Since SCP-XXXX-B's first containment breach, all testing conducting on SCP-XXXX with human subjects have been suspended indefinitely without exception. Any persons attempting to approach or enter SCP-XXXX are to be restrained or terminated depending on their distance from the cave's entrance.
Addendum SCP-XXXX.5: Incident SCP-XXXX-B-2
On 3/2/1986, reports of a lone SCP-XXXX-A instance patrolling over the security barrier were followed by a sudden power outage in the southwestern border and the disappearance of Agent ████ while at his night shift. 7 hours later, an instance of SCP-XXXX-B (presumably Agent ████) emerged from the entrance of SCP-XXXX and attempted to breach containment, causing 78 deaths and 124 injuries before being shot down by missile infantry after a 2 hour struggle. Engineers tasked to find the cause of the power outage revealed that the power generator within the site had been damaged.
Addendum SCP-XXXX.6: Incident SCP-XXXX-1
On 10/14/1986, Researcher Dr.██████ was attempting to barricade the entrance of SCP-XXXX to stop further manifestations of SCP-4405-B when [DATA EXPUNGED] By the time control of Site-██ was reestablished, 46% of security posts and containment facilities had received major structural damage with an estimated ██ deaths and 125 injuries. Several SCP-XXXX-A instances assisted Task Forces in the rescue of 82% of the missing staff. All of the SCPs within Site-██ have since been recontained, Dr.██████ and all personnel involved in the experiment, however, were never recovered. All further attempts to obstruct or neutralize SCP-XXXX were suspended indefinitely.
Addendum SCP-XXXX.8: Several SCP-XXXX-A instances have been questioned for the disappearances of several site personnel and D-Class followed by the sudden manifestations of SCP-XXXX-B instances over the the past three years since the first incident. All the entities interviewed claim to have no involvement with the incidents; however, a few of the SCP-XXXX-A stated that they know of a large, red winged male who has been behaving quite unusually ever since the first incident. So far, this target individual has resisted all attempts at communication and has evaded all attempts at capture.
All living SCPs within Site-██ Euclid or higher are to be transported to other sites to reduce the likelihood of a major containment breach as a result of a potential manifestation of SCP-XXXX-B.
Addendum SCP-XXXX.9: Incident SCP-XXXX-B-4
On 6/15/2008, the rogue instance of SCP-XXXX-A was sighted flying over the western border of the security barrier in the early evening before vanishing into the clouds before task forces could capture the entity. All personnel within Site-██ were advised to remain indoors until further notice, however Prof. Jonah Malcolm and his assistant Junior Field Researcher Margaret Ravenfield had left against regulations and were unaccounted for. Three hours after the lock down, an instance of SCP-XXXX-B (presumably Prof.Malcolm) manifested from SCP-XXXX and attempted to breach containment. The entity took flight within thirty seconds upon exiting SCP-XXXX and directly targeted onsite communications and security forces, before it began actively hunting site personnel resulting in 82 deaths and 230 injuries. SCP-XXXX-B was successfully incapacitated after Agent ██████ crashed his plane into its side, killing both of them instantly. Dr. Ravenfield has yet to be found and until further notice, will be presumed deceased.
Addendum SCP-XXXX.10: SCP-XXXX-A-1
On 3/23/2009, the rogue instance was sighted patrolling the northernmost border of the security barrier in the early morning. All site personnel were advised to remain indoors while security teams were dispatched to locate and capture the rogue SCP-XXXX-A instance. However, before the task forces could reach the target, the entity noticed the team and attempted to retreat into SCP-XXXX. The instance of SCP-XXXX-A managed to cross into SCP-XXXX's area of effect, rendering capture impossible. The entity escape was halted however when it was struck down by an adolescent female SCP-XXXX-A instance (later confirmed to be Dr. Ravenfield). The two entities engaged in a brief struggle, before the larger entity managed to pin down Dr. Ravenfield. But as the rogue instance attempted to kill its assailant, it was ambushed by two adult instances of SCP-XXXX-A and was quickly subdued. After recovering from the fight, Dr. Ravenfield killed the entity with bite to the skull.
Dr. Ravenfield returned to Site-██ to resume her work in the Foundation and submitted her research on SCP-XXXX during her absence. The following interview was taken approximately a month after the event.
INTERVIEWER: (Senior Researcher Dr. ██████)
INTERVIEWED: (Field Researcher Dr. Margaret Ravenfield)
FORWARD: Interview with Dr. Ravenfield conducted by Dr. ██████ to discuss Dr. Ravenfield's condition since her exposure to SCP-XXXX. Dr. Ravenfield is moved to a large containment cell and has been given a elevated platform designed to accommodate for her increased size with a properly butchered pig carcass hanging above keep her within range of the microphone.
[BEGIN LOG]
Dr. ██████:Dr. Ravenfield, will you please enter the containment cell.
Dr. Ravenfield: I'm coming! I coming! Ugh! You don't have to tell me how to do my own interview.
Dr. Ravenfield enters and immediately begins to investigate the perch. Paying careful attention to chew and pull on the support beams before noticing the suspended carcass.
Dr. ██████: (sighs) Margaret, what are you doing?
Dr. Ravenfield: Just making sure that this tacky piece of junk even works. No hands remember (gestures with her right wing)
Dr. Ravenfield flies onto the perch and proceeds to consume the meat.
Dr. ██████: Don't give me an attitude, young lady! This is an interview, I need you to cooperate.
Dr. Ravenfield: (growls) Alright… lets get this over with.
[END LOG]