Per 
SCP-XXXX after its recapture in 1956.
Item Number#: SCP-XXXX
Object Class: Euclid
Special Containment Procedures: SCP-XXXX is to be kept in an airtight containment chamber. The containment chamber should be fitted with a chemical dispersal system in case of a breach event. The chemical dispersal system is to be tested bi-weekly to ensure proper function of the system and that citric acids are still adequately subduing SCP-XXXX. No personnel are to be allowed into its containment chamber without hazmat suits that have been covered in citric oils. In the event that a personnel has had contact with SCP-XXXX without a hazmat suit, the personnel will be isolated for 12 hours and made to ingest 500ml of citric acids through a beverage of their preference. In the event that SCP-XXXX has attempted to or has successfully shape-shifted outside of testing, staff should commence a lockdown immediately. All staff within Containment Block██ should be sprayed with citric oils to ensure that SCP-XXXX has not impersonated them.
Update: As of 11/8/1954, SCP-XXXX vanished from its containment chamber, presumably by impersonating a staff member. It is still unclear how it escaped, as the staff associated with the incident were either slipped amnesics or took them voluntarily.
Update:SCP-XXXX was recovered on 04/15/1956.
As of 05/16/56, SCP-XXXX is to be kept in a standard humanoid containment chamber with basic furnishings. Recreational materials such as books are to be provided and may be rotated at the discretion of Dr. ████. Personnel are not to interact with SCP-XXXX unless they have consumed 300ml of citric acid or are wearing a hazmat suit. The chamber should also be fitted with a chemical dispersal system which is only to be used in the event that SCP-XXXX becomes unstable and attempts to harm staff, with the exclusion of D-class personnel. SCP-XXXX is to be interviewed weekly on its abilities in hopes of triggering a reaction. SCP-XXXX is to see Dr. Smith once per week for therapy and subtle suggestions that it may have powers in order to maintain its mental health.
Description: SCP-XXXX is a mass of black slime that weighs 68kg and has the consistency of honey. It can stretch itself several meters in all directions and consumes food by surrounding it with its body, but testing with D-Class personnel has proved it will not consume humans. Instead it chose to briefly surround the subject and then disengage, reforming itself into a perfect replica of the subject, even retaining some of the subject's memories. The discovery of its ability led to further testing, causing SCP-XXXX's transformations to become more advanced. It was capable of copying historical figures and fictional characters perfectly, even those with cartoon proportions, such as Betty Boop and Mickey Mouse. It is fond of copying the staff that tend to it and as such extra precautions are in effect to keep it from escaping or hiding in the bodies of the staff. SCP-XXXX seems to greatly enjoy these personas and sometimes refuses to abandon them. Citric acid can be used to coerce it into taking its original form. No longer effective as of its return in 1956.
Since its escape in 1954, SCP-XXXX has shape-shifted itself into a young Caucasian male 1.9 meters in height and roughly 63kg. There is nothing particularly anomalous of its appearance with exception to its large, round eyes. It claims to have grown up in a poor area of Liverpool, and has described a life there including a period of time as a Catholic monk, which has filled it with a hatred for religion and religious texts. Attempting to coerce it into its original form with citric acid is no longer effective, although it should be noted that citric acid is still useful as an inhibitor to SCP-XXXX. It displays nervous behavior when interviewed and has one occasion suffered a nervous breakdown in which it attempted to attack its interviewer.
Recovery Log: SCP-XXXX was initially recovered from a tomb in [REDACTED] on 8/2/1952. It was discovered by a team of archaeologists during excavation. According to the diaries of the excavation team, it was trapped inside a piece of pottery that had been sealed shut with beeswax. It was released when the pottery was accidentally broken while it was being taken from the tomb. The team and the locals of the nearby village were given amnesics. The recovery proceeded without incident, as SCP-XXXX was not aggressive and easily tempted into a containment module with sugar cubes.
After its escape in 1954, it was located 2 years later in [REDACTED] when impersonating a young man named ███ █████ as he served in his nation's medical corps. The Foundation discovered it was SCP-XXXX when, on a hunch, Dr.███ sprayed both Mr. █████ and his doppelganger with citric acid. All of the people who were associated with or could have had contact with Mr. █████ were given amnesics. SCP-XXXX believed that Mr. █████ was impersonating it, and pleaded with staff for an hour after being contained.
Addendum XXXX-A: Dr. ████ Test Log 11/4/52:
SCP-XXXX was left in a testing module with two D-Class personnel (D-346 and D-352). SCP-XXXX surrounded D-346 with its body for a duration of 6 seconds before releasing him and molding its body into a replica of D-346. SCP-XXXX was able to recall D-346's age, name, and his mother's maiden name without any external means. SCP-XXXX morphed back into its original form and then surrounded D-352. SCP-XXXX seemed to vanish inside of D-352 and stayed inside him for a duration of one hour before Dr. ████ instructed D-352 to drink a glass of lemonade. D-352 was weighed during this time, and had only gained two kilos of weight. SCP-XXXX emerged eleven seconds after D-352's consumption of the lemonade and displayed sluggish, lethargic behavior for a period of six hours.
Addendum XXXX-B: Interview on ██/██/53
Addendum XXXX-C: On ██/██/1956 SCP-XXXX complained of severe stomach pain to staff for several days. Medical staff ran tests on it and discovered that its transformation was so complete it had human anatomy down to the cellular level and was suffering from appendicitis. The decision was made to perform an appendectomy to relieve its pain. The appendix was preserved in formaldehyde for later study, but within 6 hours of being removed from SCP-XXXX it reverted to black slime, hereafter referred to as SCP-XXXX-a.
SCP-XXXX-a lived for a total of 2 hours, in which it displayed listless behavior before hardening into a grey, flaky material which has been stored for further testing.
Addendum XXXX-D: Interview on 06/6/56
