Per 
item #: SCP-XXXX
Object Class: Keter
Special Containment Procedures
SCP-XXXX must be kept in a 5mx5mx5mx5m containment chamber. Any attempts to let out SCP- XXXX are strictly prohibited and people that do so are to be exterminated immediately. Any testing on SCP-XXXX Must be authorized by at least 1 05 council members and must be escorted by highly trained MTF guards.
Description: SCP-XXXX Is a humanoid figure standing roughly 6 feet tall. SCP-XXXX Appears to be made out of a gas which is currently unknown to foundation personnel but it is highly likely to be but it is similar to shadows. SCP-XXXX takes human hostages and possesses them for 24 hours to when it kills the host and looks to find a new one,slowly killing everything on earth.
Addendum-1- Test 134-A
Doctor _ : today you will be doing your last test then you are free to go!
D-9347: yea, whatever lets just get this over with!
Doctor: _ : very well then continue into the chamber!
D-9347: ok yea so what this some kinda ghost, or demon or some endless supermarket what's the deal here!
Doctor _ : everything you need to know is in this document
D-9347: (reads document) k well at least this is my last one!
D:9347: (enters containment chamber)
Doctor: _ : now walk towards SCP-XXXX
D-9347: ok but how is it gonna-
SCP-XXXX: (takes D-9347 hostage)
Addendum-2-Update
New research shows that SCP-XXXX is able to speak a variety of languages when possessing a human hostage.
