131-GREY is a 131 instance, boasting a dark grey colour. There are no abnormal visual differences between this instance and the others,aside from the striking dark colour; no GREY-STRIPED has ever been recorded. 

131 GREY has a few abilities that set it apart from other 131 instances. It has the ability to create fog, a light that is unnatural for 131 instances, of which is a dim blood red. Besides that, it can do the following. 

• Kill personnel via their ‘Fog’

• Possess Anomalies

• Blackouts/Flickering

Due to 131 GREY’s murderous tendencies, personnel are advised to respect 131-GRY at all times and call them "The dark one" Not doing so may result in confrontation from ETA-9.

SCP-131-GRY or the "Dark one" as it likes to be called this way needs to be summoned through a specific summoning ritual, see Addendum 131-GRY.1
SCP-131-GRY does not have a containment chamber due to his reality-bending abilities. At no point during testing should research personnel doubt or question SCP-131-GRY's abilities. In case, someone questions or doubts SCP-131-GRY's abilities, it will then promptly display its abilities to whoever asked or any bystanders.

SCP-131-GRY is able to possess other anomalies and control them. Typically SCP-131-GRY will possess SCP-662-1 as it is the most obedient one out of all the anomalies contained on-site.

SCP-131-GRY is to be treated with caution, as SCP-131-GRY can be classified as a living lethal weapon with a god complex, angering it will cause it to breach and cause havoc around the site.

In the event of a breach, MTF Eta-9 "Wardens" need to be contacted immediately, they will have maximum authority. Foundation Personnel are to listen to the given directions and have to watch out for sudden blackouts or apparitions of red fog.

Re-containment of SCP-131-GRY is to be primarily conducted by Eta-9 operatives. The process of re-containment is done by "Banishing" SCP-131-GRY. The process of "Banishing" is done by trapping SCP-131-GRY in a pentagram of candles and then "Sacrificing" someone who has consumed SCP-1200-15.

Following the Decommission of the Specialized Research Team and the increase of SCP-131-GRY activity, the Testing Manual doccument will be Declassified to the public. 

The following text was taken from a book found in Sector 2 in Sublevel-4 of Site-40

Page 112

"SCP-131-GRY is a complicated being with conflicting origins. To start off with our lesson, SCP-131-GRY wasn't always a SCP-131 instance, but a being of pure evil and power. While the original appearance is unknown, what we do know is its creation. The tale is as follows: Many centuries ago, SCP-343 needed support to be the "savior" he claims he is; he did this through the creation of 131-GRY. SCP-131-GRY was instructed to attack only SCP-343 and his followers, and with a show of mighty strength to the public, SCP-343 banished it. But this isn't where it ends. SCP-131-GRY lived, and it grew stronger. SCP-131-GRY received new power through the form of human sin. It was so bad, in fact, that SCP-343 couldn't contain it anymore, so as a last-ditch effort, SCP-343 transformed SCP-131-GRY into a SCP-131 instance and searched for a place to keep it isolated. This is where the Paragon Research Institute comes into play. Every time SCP-131-GRY comes out of banishment, it regains power when it's in the real world, so SCP-343 gave SCP-131-GRY to us with knowledge of how to banish it every time it rises again." (Dr. A Gren 112)

Cognitive Questions:

1. Would you still have trust in SCP-343 for creating SCP-131-GRY?

2. Do you believe that we are truly to blame for SCP-131-GRY's rise in power, or is it an excuse?

3. Would you consider that SCP-343 gave SCP-131-GRY to us so that we would do his dirty work?

-Dr. Astrid Gren's book of abnormalic expertees.