Yes certainly. Forgive me I didnt know. What's wrong with DeviantArt? If I may ask?
Here's the direct copy and past of the theory so forgive any additional details that where dA specific:
The majority, if not entirety, of the game 'The Evil Within' features STEM as it's focal point, whether you're in it, trying to get out, or simply learning about it. STEM plays a strong key role. Many have come to find themselves lost or confused about The Evil Within, sort of like the victims of STEM. As a result, I have decided to conduct my own 'research project' of sorts and decided to attempt to decode this enigmatic game, hopefully clearing some things before the DLC's release and revelation. So this report will focus on STEM itself and just some of the things it's capable of. Hopefully this will enlighten people on certain key aspects, develop more theories, or make for an interesting read. If you have any thoughts, opinions or anything to add onto my theories, or maybe query the uncovered, comment please. I'd love to hear your ideas. I will be crediting others theories or confirmed information if I use it. That way it's fair and original credit can be given to the right person. Without further adieu.
What IS STEM?
This is the first and forth most important aspect to consider and understand before delving further - knowing what exactly IS STEM? STEM is a seeming enigmatic machine that is "the brainchild of Ruvik". It is also the machine he was forced inside, along with many other characters including the protagonist, Sebastian Castellanos, and the doctor responsible for stealing Ruvik's ideas, Marcelo Jimenez.
Appearance wise, it is a machine with bathtub-like terminus' to connect minds together, along with the host mind (usually in the centre of the machine or the first to be attached to STEM and simulate their own 'mindscape'. The machine is known to have a build-in life support to maintain the lives of those within STEM, and external interferences to further support the lives of the subjects. Ruvik's mindscape STEM appears to be more skewered forms of this device, bloodied, or even a metaphorical image (a large central brain with various painful devices to depict him mind and physical brain, fluids for preserving, and cords to connect the psyche). This is possibly due to Ruvik viewing 'Mobius'' STEM as a "perversion" of his own device (stated in the final audio log, which I have uploaded transcripts to on the wiki).
Who created STEM?
A small and blatantly obvious answer, STEM was designed and created almost entirely by Ruvik alone. He knew exactly what he wanted and envisioned. He knew exactly what it had to do and why. Jimenez's role on STEM was almost restricted to providing Ruvik with easily accessible test subjects. Originally, Ruvik captured his own, however this brought much awareness to his actions to the Elk River village, and was seemingly a more time consuming and tedious method. Subjects were instead 'borrowed' from Beacon as these minds were different, unstable even, and allowed greater access. Most patients were possibly abandoned by any living kin, resulting in their disappearance meaning next to nothing and their unknown existence to society makes for a greater host as if they are freed, no one will have much knowledge on them thus no abnormal behaviour could be detected. This is where most of Jimenez's contribution came from. Ruvik was more than intelligent enough to create STEM alone, but his family history of being connected to the asylum furthered his plan, made it easier. The time they worked together presumably started when Ruvik was 18, Marcelo's discovery of Ruvik's killing was possibly the catalyst to offer his patients to the man's research.
Why was STEM stolen? And by who?
After years of working together, Marcelo began to fully witness the blossoming intelligence of Ruvik in it's adult state. Despite no formal education as such due to hid wealthy upbringing, Ruvik clearly displayed intellect far surpassing that of the doctor. This is what pushed the doctor to his plans. Originally, he had somewhat nurtured and encouraged Ruvik's mind but upon seeing that his 'student' could easily surpass him without the formal academic training that he had to undergo himself is implied by Ruvik's flashback to have left him bitterly envious. Marcelo saw great potential from Ruvik's contraption, as well as a genius mind behind it. To not appear foolish and to gain credit (and possibly some vengeance on Ruvik for his intellect) Marcelo took to co-operating with the mysterious organisation, 'Mobius'. Here is left up to speculation how long he worked along side them before betraying Ruvik, as well as what lies he told them but I do have some suggestions.
It is highly likely 'Mobius' is to believe Marcelo was the maker as he has the academics and was not shut away or implied to have experienced any psyche crippling trauma - opposing Ruvik. Also, Ruvik towards the end of his physical time dressed rather eccentrically - the robes he wore in STEM. This would further the 'mad man' look. Also due to Ruvik's experiences, Marcelo could easily claim to the agents that he was mad (although this wasn't exactly incorrect, Ruvik could still function somewhat) and thus claimed that this machine could test to 'heal' him or use his 'unrecoverable mind' to 'heal' others. He may have even revealed that Ruvik is intelligent but unstable, so he invented the machine to preserve the intelligence and remove the 'illness'. Either way, Marcelo stole it selfishly for his own needs. Whether he claimed the work of STEM to truly be just his, or create a role reversal (giving Ruvik credit for his own role, and himself credit for Ruvik's role) is unconfirmed. Although possible, it is unlikely he gave Ruvik the true recognition he deserved. Another aspect that supports the idea that Marcelo could have used Ruvik's instability as an alibi that Ruvik was not the sole creator is that he set traps around his home to prevent intruders getting in. Marcelo could - as a doctor - claim paranoia and psychosis (a real life example would be paranoid schizophrenia) to justify Ruvik's actions as sole madness as opposed to extreme (although unstable) caution. Marcelo may have furthered this 'excuse' by telling the agents of non-existent delusions (a symptom of psychotic behaviour) that he invented STEM, as - in the agents eyes - evidence points against Ruvik. The audience however, is gifted with the truth. After this, the agents helped to dissect Ruvik, removing his brain as the desired prototype testing for STEM, and burning his home to destroy remaining evidence of both the events of the years of STEM's development, as well as Ruvik's existence to the public. Marcelo's act of ridding Ruvik may be to 'kill' him off and take the credit.
'Out of sight out of mind'
How does STEM work?
STEM works by using it's Bathtub terminus filled with fluid to firstly contain subjects as well as preserve them during their time within the 'virtual reality/brain stimulation' of sorts. Subjects are connected to the device whilst lying in one of the terminus', to which an umbilical cord like tube is 'plugged into the brain of said subject. The machine then acts as a stimuli to the brain, creating a sort of 'reality' consisting of the subjects raw memories which are stored within the hippocampus of the brain. This direct stimulation mirrors virtual reality as it 'tricks' the mind into believing the subject is within reality. This may also explain as to why the subjects may succumb to cardiac arrest within STEM. Due to the brain being directly connected to the machine, the external manipulators of the machine can (presumably) get access to the mind and data stored within it. They may also essentially 'guide' a subject into connection with the other minds or to a degree of understanding. The 'mindscape' created becomes a metaphorical plain based on the psyche and perceptions/interpretations of the individual, however 'host' or 'dominant' psyches usually retain the land, being the first one connected they create their 'world' first which covers the 'plain'. Other minds join akin to a sort of 'chatroom' to meet and understand the psyche, a possible synchronisation or 'fusion' occurring with some which allows full body possession, sharing of a vessel or a possible 'swap'. The host was Ruvik at first who was a brain (presumably in the centre of the machine), however the host is usually the first to enter as proven by Sebastian (after the implied exit of Ruvik/Leslie an Juli, he is the sole 'survivor' of STEM, making the world now his), meaning the host does not have to be stripped of their real forms. The machine also has an 'in-built' life support to monitor and maintain the life of each subject. The number of terminus' depends on how many subjects minds can be connected at once. In the real-world, STEM appears mostly white, clean and sanitary unlike the rusted ones in Ruvik's world.
As the brain is the most enigmatic organ and still many factors are undiscovered, many believe the brain may hold psychic abilities or 'connections' made naturally between people (some proven in real life research). The brain is also strong, complex, yet fragile and easy to manipulate. Many people can trick themselves using cognitive functions or 'manipulate' the area (small range) around them. This ability is possibly what explains Ruvik's capability of small range external manipulation of those using/involved with STEM. This would somewhat mirror the effects of radiation and its poisoning ability, if an analogy would be easier to envision the ability.
STEM's capabilities/What does 'Mobius' want?:
As reported on The Evil Within Wikia, STEM can perform a numerous of tasks including: synchronising minds together, curing of mental illnesses, learning others memories, and interrogating criminals. These may what 'Mobius' sought when Marcelo proposed the idea to them. STEM to them is like a miracle machine. If Marcelo only revealed it can synchronise minds, 'Mobius' may have came up with other uses for it, becoming infatuated with the conception. There is also possibility that Marcelo himself may have came up with other, more generic and to a degree 'public' uses for it, sharing it with the organisation and working with them to make it public possibly. It's possible 'Mobius' wanted to make STEM public eventually once they dealt with Ruvik. They possibly was going to advertise it as some 'miracle' machine, without truly knowing the costs and capabilities. Only the original creator - Ruvik - would know what to do with it. Whilst Ruvik remained within STEM, his only means of revenge was moderate sickness externally, and killing those who internally entered - willing or otherwise. As a result, all the claims that it was supposed to do could not be proven or disproven until a truly compatible mind presented itself. A mind who had an equalising manipulation in his world, and a mind who could traverse back into the real-world. This mind would be Leslie. For STEM to begin functioning efficiently for 'Mobius', the hosting brain would have to be of a stable one. Ruvik's mind was not this, nor did he ever intend this as his goals were different to the organisation.
STEM's intended purpose:
As the creator of STEM, Ruvik intended the machine for his personal use and knowledge alone. It was a project of secrecy, no one was ever supposed to learn of STEM. Whether he planned to eradicate it after it's purpose or not is unknown, chances are he would have continued it's use into further research into others. As revealed by an audio log, Ruvik planned to 'restore his face' and 'redeem' his sister, Laura. This further denotes Ruvik's poor self-image - he saw himself a monster not only (as a child) for his 'gross' experimentations, but also later one for his heavily disfigured skin. 'Regaining his face' he desires to looks physically appealing, or at least free of heavy scarring caused by the fire. One reason for this is presumably his upbringing, in which the upper class would always be expected to look their best, especially in public. His father also hid him for these scars, making Ruvik, in simple terms, feel hideous. The scars also left severe bodily harm, not allowing proper temperature regulation of the body (and possible poor hydration, requiring a higher consumption in fluids to replace the rapid loss of water in the skins cells). What is bizarre however, is his refusal at the age of 18, of skin regeneration therapy. This may be caused by the scars that would still remain afterwards which may forever serve as a reminder. To simulate his consciousness in another compatible mind, he can be granted a fresh start and a 'pure' body to continue his work with. To regain Laura may be to place her through the same process: remove her psyche and place it within a fresh, non-vegative host. This would be to preserve her life (as an in-game newspaper suggests she survived the fire but was left in a vegative state. Ruvik could have discovered this and saw through his father's deceit but kept quiet). They would both be able to start a fresh new life, 'free' of most of their past traumas. Also due to the physical host no longer being of biological relation, Ruvik may have been able to court his own sibling and undergo a societal acceoted marriage. The lack of close genes would also decrease chances of deformed children. This is possibly over analysis o my behalf.
This would not only give them new life, but also a chance at revenge for the wrong committed to them. Ruvik initially created it for a swap of bodies (this may have made the unfortunate villager have to live with his scars) but due to later being dismembered and placed within STEM as a raw brain, this fuelled not only his revenge, but his desire for a new host. This desire boarded onto desperation as he sought not only a 'clay-like' mind to mould as himself (yet a strong psyche to endure his psychological traumas), but also a mere physical host to be free and whole again. This almost justified his actions more rationally than his original intentions. Some also speculate that due to his isolation - both from society and an understanding figure (sister) - he also had a secondary purpose of creating the machine to emotionally connect and 'bond' with others. Getting them to understand him, pity him and give him the love and understanding he was deprived of. My theory is, if a FEMALE subject displayed these traits in his world, plus the 'clay' susceptibility and strong psyche, she would be the candidate for Laura's consciousness. This would imply his lonely nature and inner desperate child.
Sorry if its a poor theory ^^'
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