- That would explain the huge insects and stuff. Maybe the other humans you see are a tiny, previously undiscovered race of Lilliputian people, or others that have been shrunk.
- It fits the description pretty well.
- The Boy caused the death of the Girl, probably from a practical joke gone horribly wrong. The other children represent the Boy, they lay deadly traps as "practical jokes" and trying to kill the Boy. The giant spiders and insects represent fears of spiders and insect the Boy (or maybe the Girl) had.
- The sister is a dream fusion of his dead mother and brother.
- The rotting corpses seen under the treehouse could be a particularly sour interpretation of the graves under the tree in his dreams.
- The final fight with the spider is a clear link to the fight with the spider monster that killed his brother.
- The images of hanged people could also be the result of remembering the more horrid parts of the journey (especially if the suicidal man is not saved).
- His fear of water is naturally increased in his nightmares.
- The older children attacking him are a logical progression of the vision he had of Naia strangling him - now multiplied and even darker than before.
- And fundamentally, all the Boy's violent deaths would be Naii taking out his self-blame on himself in the dreams.
- The tree house was their tree house. There were two brothers who lived in their neighborhood, one big and one small, who were always mean to the Boy and Girl. The brothers went up into the tree house and wouldn't let the boy and girl in. When they tried to climb up the ladder, the brothers cut the rope ladder and they fell, breaking their necks on the ground.
- The brothers are the first two humans you see in the game, the ones that roll the burning trash down the hill. The other humans in Limbo are different forms of the two, each trap representing a way they would bully the boy and girl.
- The rope ladder is severed and there are two corpses lying at the bottom.
- The brothers either ran away after realizing what they did, or they were stuck in the treehouse and starved to death.
- The boy is actually hallucinating, which is some sort of limbo between sleeping and being awake. The entire adventure was actually the boy stumbling around. That's why the boy never runs out of lives; he never died in the first place. The fall through the barrier in the ending represented him waking up. The title screen is actually another hallucination.
- The kids were playing at their treehouse. While the girl decided to clean the meadow beneath the tree from constuction debris they left, her brother tried to find out how far can he venture by the branches above ground. Several trees to the left, he noticed some bird's eggs in the nest and tried to reach them, but the branch snapped and he fell to the ground and was knocked unconscious. The title screen represents the fear of death he felt during his fall. His dream started with the feeling he's got to get back to his sister and gradually turned into mishmash of all horror movies he ever saw. The brain worms represent his subliminal thoughts of sleepwalking. Him respawning after each death is him simply "replaying" that portion of a dream over and over until he succeds. In the end, he finally wakes up and, still stunned from the fall, stumbles back to the threehouse, and startles his sister who didn't expect him come from that side, as she thought he was still in the treehouse.
- Not only did the Boy have Blob, but he also had a sister and another smaller treehouse. He wanted to show his sister that treehouse but we all know what happened.
The Boy's spirit, unable to rest because of this grisly fate, searched through a Self-Inflicted Hell to find his sister. He may have believed her to be back at the factory, and thus took his trip in reverse to try and find her. Besides the mind control worms (representing a lack of freedom he experienced at the factory), the things that prey upon them (representing defiance to that lack of freedom), and the spider (represented as a huge monster because it killed both him and his sister, and was warped by his perceptions and expectations as a child of what a lethal threat should look and act like) things remain relatively realistic through those parts of the game. And then he reaches the factory.
He finds his sister, but cannot reach her due a mind control worm. When he gets rid of it and returns, she and their treehouse are gone, replaced by more of the mechanical hell that came before it. It may be at this point where his mind begins to crack under the stress of not finding her, and things start to mesh together. From that point on in the game, it cycles through far more surreal versions of the forest, drains, city, and factory. While technology remained mostly (the neon hotel sign being a possible exception, but it is hell after all) consistent for the potential time period up until this point, things start to change, and technology that did not exist at the time of the Boy's death begins to appear (electric rails, machine guns, high tension cables, anti-gravity generators) along with things that break physics as we understand it.
It quickly turns into an insane smashed together version of every area, and near the very end the direction of gravity begins to switch on its own, showing the true breakdown of reality as it exists in the boy's eternal punishment. He breaks through a wall of glass, symbolizing his mind fully breaking under the stress of it all. He can finally take no more, and just creates an sublime area in the forest with his sister and the treehouse to try and realize his goal. But it's just a lie, and he knows it. He awakens in the dark forest once more, his only memory being that of a sister he wishes to find. So the tale starts anew, with no other memory of before due to being mentally broken each time, and the boy goes looking for his sister again and again. Forever.
- Well, there are child soldiers in the game after all.
Because the boy died, he must travel through it, but even though he's just a child, he is not exempt from the purifying process; it must be impersonal in order to fairly accommodate everyone who goes through it, and show no favorites. Thus, while journeying through Limbo, the boy confronts his fears. Among them are: bear traps, spiders, bullies (the shadowy figures he encounters who are constantly trying to kill him), someone taking over his mind (the mind worms; perhaps he was frightened by a magician who said he could hypnotize the boy) fire, drowning, electrocution, heights (the top of the buildings), big impersonal buildings (factories), loud machinery (buzz saws), darkness, loneliness, guns, and disorientation (gravity switches). Once he manages to overcome these obstacles, the boy falls back into Limbo's neutral state (ground with nothing about it). While falling, Limbo reforms itself into a forest, and from there, the boy is allowed to pass on to whatever lies beyond limbo.
While journeying through this world, the boy must continuously head towards the light, as it represents God/purity/heaven, and is used as a good thing throughout the game (either in showing the way the boy has to go, a butterfly of light leading him in the right direction, burning mind bugs, the shaft of light that shines on the boy while breaking through the glass, etc.). Because none of the other children have light in them (the eyes) they are not real, and manifestations of the boy's fears. It is unclear if his sister his imaginary (she could be a manifestation, or we are simply unable to see her eyes), but upon reaching her, a sharp beam of light shines down on them both, suggesting that the boy can move on.
Based on this theory, and on the obstacles the boy confronts, it can be theorized that he lived in the suburbs near a giant forest, and a large city. He was bullied constantly, his father was a hunter (based on the bear traps and guns), the boy occasionally ran into spiders while playing in the forest, which was also where his beloved treehouse was. His mother lived in a factory that he once visited, only to find terrifying, and subsequently never went to again. One day, while out in the forest with his sister, something happened that killed either both of them, or just the boy (if it was just the boy, he wouldn't know that his sister died), and upon waking in Limbo, finds himself in a world that's been exaggerated to accommodate his fears.