Soren was either born on the colony Dwarka in 2511 or moved there as an infant. When he was six years old his mother died of an unknown planet-specific sickness because his stepfather refused to take her to a doctor because he was running an "illegal farm" beyond the limits of the lands authorized for settlement, and was afraid of being caught. By the time his stepfather realized that she was mortally ill it was too late to take her to a doctor and she died. The stepfather refused to accept this and kept the mother's body in a locked room in their house, telling Soren that she was sick and needed to be alone to recover. One night when his stepfather had too much to drink, Soren stole the key to the room and found his mother's decomposing body. He came to the conclusion that his stepfather was responsible so later that night he stabbed him in the neck intending to kill him, hitting him between the neck and clavicle. The stepfather survived and Soren ran into the forest surrounding his home. After this Soren lived off the wild and watched his stepfather. During this time he adapted himself to live in the wild eating berries, worms, and grubs.
One day he saw that his stepfather was sick with the same illness his mother had died of. When his stepfather collapsed on the way to his field Soren finally revealed himself to his stepfather and instead of getting him medicine, he watched him die. He then buried his mother and stepfather, and after staying in the house for a while, he trekked 112 kilometers to the nearest human settlement where he was placed in the care of social services. He never told anyone exactly what had happened to him. Instead he simply said that both his parents had died shortly after each other, and after several months living alone he set off to find civilization.
When Dr. Halsey came to Dwarka to observe Soren she openly gave him the choice of whether or not he wanted to join her "experiment" or stay on Dwarka in foster care. Soren chose the first option, and immediately left Dwarka with Halsey and Lieutenant Jacob Keyes.
During Spartan training, Soren tried his best to simply "blend in"; to neither excel nor fail, simply to remain in the anonymous middle. Soren also proved himself adept at blending into the forest during training exercises. Dr. Halsey watched him closely, and on one occasion told him "Don't let yourself get left behind," words which would resonate deeply with him. At one point he preferred to sleep on the ground underneath his bunk and after he had slept for too long and all the other Spartans had woken, they had seen him sleeping under his bunk and gave him a confused look.
Prior to the SPARTAN-II augmentation procedures, Dr. Halsey once again asked Soren whether or not he would like to participate. Confused, Soren asked her why he was the one selected to make the choice, to which Halsey replied, it simply turned out that way. Knowing the risks, Soren chose to participate, stating that he "did not want to be left behind."
During the augmentation process, Soren dreamed of a hulking, deformed creature pursuing him through a forest, occasionally giving out a cry of pain. The creature eventually caught up to him and smashed him. Soren awoke during the augmentation process, but fell back asleep into another nightmare. This time, he dreamed of lying on his mother's bed, the same one she died on. His stepfather was in the same room, described as more shadow than man. During this dream, another figure, his dead and rotting mother, was in the same bed, when a sudden wash of pain, like broken glass being worked into his veins, woke him up again.
When he awoke, he was restrained to the bed. A doctor attempted to give Soren a hypodermic injection, but he broke the man's wrist, stabbed another doctor in the neck with the needle, and punched a third as he fled, sending him flying into a wall. Soren then tore himself from his restraints and attempted to run. During his escape, he was stopped by Chief Petty Officer Franklin Mendez and a squad of UNSC marines armed with tranquilizer darts.
After awakening again, he was in a brig, now chained by titanium wrist-lets. He was visited by Dr. Halsey, who informed him that he had been in comatose for three months, and his body did not react as planned to the muscular enhancement injections and the thyroid implant, which had caused his muscles to grow in ways that were unpredictable. Only by using the carbide ceramic ossification process was he saved. One leg was more or less normal, if a little bowed and twisted, however the other was severely gnarled and about six inches shorter. His arms were incredibly muscular, painfully so, giving him the greatest upper body strength of any Spartan. The fingers of one hand were twisted and bowed, functioning more like a pincer or claw. To deal with the intense pain Soren was given massive amounts of painkillers, however he did not like the way they clouded his mind, so he gradually weaned himself off them.
Soren was incredibly disappointed when Mendez told him that he couldn't certify him for active service. Mendez told Soren that if he were to join a team of other Spartans, they would constantly be reminded of the Spartans which didn't make it through the augmentation procedures, and they would see it as their responsibility to keep him alive, thus hurting their focus and ability to perform. Additionally, there was no body armor which would fit his unique physique, and his deformed hand made it too difficult to fire a weapon. Against his will, Soren was relegated to a desk job, similar to Fhajad-084.
Insurrection and MIA
Although his superiors assured him they would find a better fit for him, Soren remained a paper pusher until he was sixteen. As his "temporary" position began to feel more and more permanent, it became hard for Soren not to feel resentful. This made the young Spartan particularly vulnerable to the ideas of a technician named Partch, who began feeding him ideas sympathetic to the Insurrection. Instead of reporting Partch, Soren listened. Slowly and almost imperceptibly, his views changed until he found himself on the side of the rebels.
After several months of hinting, Partch told Soren that they were going to defect, but first they were going to obtain a "souvenir" for their cause. One night, the two broke into a geological research lab, forced open a locked cabinet and retrieved a small titanium case. However, they were interrupted by Randall-037, another Spartan. Randall was justifiably suspicious of their explanations, and escorted them out of the lab so that he could verify that they were supposed to be there. As they left the lab, Soren attacked Randall, and as the two struggled, Partch shot Randall with a tranquilizer dart. Soren and Partch then fled the facility and commandeered a Longsword fighter which Partch had pre-prepared and hacked, complete with a dumb AI named Captain Teach whom Partch had fast-grafted to convert him to their cause. Their plan to escape Reach failed, however, as they were pursued by other aircraft, which sufficiently damaged the Longsword to prevent it from breaking free of the planet's gravity. Captain Teach and the backup computer system were damaged or destroyed, forcing Soren to manually crash-land the craft himself, breaking Partch's neck in the process.
When Mendez and his Marines found the wreckage, relatively little was left, the only thing of note being Partch's burned body. Dr. Halsey told Mendez that she believed Soren had survived the crash, but due to his upbringing in the woods, Soren would not be found unless he wanted to be. Halsey had Mendez give up the search, arguing that Soren was no threat to them: he was not a traitor, just a lost soul. Without a body, Soren was officially declared Missing in Action.
Soren described himself as being different than the other spartans, but didn't know what it was about him that was different. As a child he was consumed by a desire for revenge against his step-father, whom he considered to have killed his mother by not taking her to get medical aid. During his troubled childhood, he also seemed to have an unusual attachment to his house, which he could not enter nor leave. Years later, his views would change, as he would no longer consider himself to be a monster, but a very flawed human.
- In Pariah, he is referred to as "Soren-66"; however, according to SPARTAN naming conventions, he would actually be Soren-066.
- Soren-066 is the only known SPARTAN-II to volunteer for the program.