Per 
Item #: SCP-4254
Object Class: Keter
Special Containment Procedures: SCP-4254 is to be contained at all times in a 3m x 3m x 3m chamber made of steel 5m thick, and kept at temperatures no higher than -50°C. The inside of the chamber should have no less than 6 sensors in order to identify any possible movement from SCP-4254. SCP-4254 is to have no contact with any lifeform, and its chamber is not to be interacted with in no way whatsoever outside of scheduled maintenance.
Behind SCP-4254 there should be a remote controlled steel blade. Should movement be detected inside SCP-4254's chamber, the steel blade is to be driven into the back of SCP-4254's neck and up into its brain stem, incapacitating it. Afterwards, at least one (1) D-Class personnel is to be sent to investigate the chamber to identify (and if necessary, repair) either a faulty sensor or faulty temperature devices. 15 minutes after SCP-4254 is incapacitated, D-Class personnel must evacuate the chamber before SCP-4254 regains consciousness, or the chamber be sealed off.
Description: SCP-4254 is, superficially, a standard human being, with all physical human features present. In reality, however, SCP-4254 is anything but human. SCP-4254 appears to be incapable of speech, as it has never been heard communicating with anyone or anything. SCP-4254 also appears to lack all sort of human emotions, and seems to have a sole directive: kill everything it sees.
SCP-4254 is also physically nothing like a standard human. SCP-4254, for starters, seems to be immortal and indestructible, although it can still be damaged, albeit not permanently. Upon taking damage, whether it be blunt, sharp, small-arms or explosive damage, SCP-4254 will be stunned for about a second, before almost instantly repairing any and all damage it has suffered.
SCP-4254 also seems to be able to restructure its arms into a variety of tools at will. SCP-4254 has been seen using basic tools such as levers and wedges to stab, cut, or even pry open as it would require. Along with basic tools, SCP-4254 can also conjure more advanced, usually electrical, tools such as saws, and on one occasion, a firearm.
SCP-4254 is seemingly capable of generating energy as well, usually in the form of electrical or thermal energy. It can restructure its arms into one of two strange, unidentifiable devices: one can be used to either connect to an electrical grid or an electricity-powered object and supply it with power, or it can alternatively use the device to launch arcs of electricity, which are of course, incredibly dangerous. The second of these devices can be used to generate incredible amounts of heat, enough to melt any living being instantly, and enough to melt through even the strongest Class-5 Diamond-Reinforced walls, given a handful of hours.
SCP-4254, although indestructible, can still be incapacitated, both temporarily and permanently. SCP-4254 is, for as-of-yet unknown reasons, weakened by cold temperatures in a declining fashion, becoming weaker as temperatures get colder, although still remaining incredibly powerful, that is until temperatures reach precisely -50°C, at which point SCP-4254 abruptly enters a state of complete shutdown, and will remain like so until temperatures rise over -50°C, at which point SCP-4254 will continue operating at its (seemingly) most minimal capacity. A more temporary incapacitation method, to be used only for emergencies, would be to impale SCP-4254 with a strong, sharp, and long enough blade at the back of SCP-4254's neck, and reaching up to it's brain stem. This will also, for reasons as-of-yet unknown, disable SCP-4254, albeit for approximately 15 to 20 minutes. Bullets would not function, as SCP-4254's skull seems to be strong enough to block all ballistics so far used.
Due to SCP-4254's hostility to everything human and man-made, studying SCP-4254 has been incredibly difficult. To make things worse, it would appear that any piece of SCP-4254 detached from the main body of SCP-4254 is instantly destroyed, making analysis of samples so far impossible. This, however, has not prevented scientists from formulating theories about SCP-4254's cellular makeup. Some reaserchers believe SCP-4254 to be constructed of advanced nano-machines. Many other researchers believe SCP-4254 to be an incredibly advanced android (either escaped or intentionally released has yet to be decided) manufactured by Anderson Robotics, though this has yet to be confirmed.
Addendum 4254: Discovery
SCP-4254 was discovered when a hiker, identified as █████████ ██ ███████████ ███████ discovered a dead body by the mountain trail through which he was walking. After further exploration, Mr.███████████ found a man wandering around with his hands covered in blood. Mr.███████████ hid from the man, and as quietly as possible, alerted the authorities. After the authorities arrived on the scene, [DATA EXPUNGED]. After a few minutes, Mobile Task Force Epsilon-6 arrived on scene, [DATA EXPUNGED]. After SCP-4254 had finally been subdued, [DATA EXPUNGED], and SCP-4254 was taken into Foundation custody.
