“Everything Ends. And So Our Story Begins.”

First things first, let's go over the Whole Thing.

SECTION 1: Simon stares at his bloody hands, as a kid (you can tell by the sleeves). Cut to him surrounded by bodies. Adjusting the image brightness, you can see they are the same kids from the Grove scene earlier. Then his adult hands, also bloody.

SECTION 2: A short scene of a woman (we infer it's his mother) handing him the knife holster, WITH a knife on it. It's notable that we don't see an actual knife anywhere else in the movie, only the holster.

SECTION 3: I gifed this part because the camera work is important. the other sections were in clean cuts and static cameras, but not this one. The camera turns locked to Simon's dazed face. One of the kids, calls to him from behind. He turns, and now it's an adult voice shouting at him to "don't just stand there, do something!" It's a grown man now. A great wall of fire from an explosion burns through the hallway and consumes the man.

Sequence ends and we're back in going-around-in-circles land.

Now, to the speculations. I want to point out that I will raise a number of possibilities here, and how they can work together. As for my own personal interpretation, I'll get to it in another post, so this one can be used as reference and for lore-buiding purposes.

Being a dream, we can't take everything literally. Simon is already losing track of time and the order of events in the real world, and dreams are naturally murky. This does however establishes a few things.

The first section it's pretty cut and dry. Simon has had blood on his hands since he was young, and he feels to blame for what happened to his brothers and Eden. People he was close to are dead, or he believes they are, and he believes it's his fault. It serves as foundation for the other sections.

For his mother giving him the knife, we do not know the exact purpose or intent behind it. It could have been an innocent handing down of an heirloom, or something for him to protect himself, since he's had the holster prior to the Quiet Rapture. We do not know when Eden took the turn into the death cult route, it could have been before the Rapture or immediately after.

Regardless, I'm not entirely comfortable assigning the handing of the knife as entirely cult behavior. Not to say Simon's mother is some naive angel here, she did hand a combat knife to her son at a very young age and he wears it prominently. Not on his belt or boot, but on his shoulder. It's a combat-ready positioning for a dagger. It implies that if this did come prior to the Rapture, the Mars colonies weren't peaceful to begin with and prepared its people for violence since youth. By that metric, turning into a violent death cult isn't that big of a jump.

For the hallway scene. It's hard to see, but this kid has blonde hair and black straps on his outfit, meaning it's the Brother on the far left of the Grove scene. Let's call him Second Brother. The way he's almost as scene-forward as Simon in the group, could imply a few things:

They are of similar age;

They are of similar importance to Father;

They are both high in the hierarchy of the group, possibly leaders;

They were close to each other;

The way Second Brother melts into the Adult Brother heavily implies they are the same person. If we assume they are, then Simon did NOT kill his brothers as children, otherwise they couldn't have grown up to haunt him in his dream. The dead children scene is then metaphorical, he blames himself for their deaths and it taints his memories of their youth.

That said, let's consider the option that he did literally kill them, directly or not. The Adult Brother then is someone he views similarly as Second Brother, either in rank or in closeness. Someone he also killed, even if indirectly since it's heavily implied his inactions are to blame for the death of the Adult Brother.

Now, that somewhat contradicts Simon's later recounting of events, but lets put down what we can somewhat safely assume:

Second Brother and Adult Brother were very important to Simon;

They are dead or Simon believes they are;

They were involved in the attack on Filament Station.

I've also considered if the Adult could have been COI instead, but there's no badge on him, and we know COI loves their badges.

To what this offers in context to the next reveals is very interesting. Simon's short loredumps of the Filament Station make for some interesting stuff.

When talking to the Voice/Elli, he shows some disregard for life and survival. Everything is gone and there's no bouncing back from the Quiet Rapture, so why does anyone care if a station and several people are also gone? Who cares about who dies and who lives, if everyone is not going to make it anyway? That is death cult mentality, and clearly a frustrated coping mentality to Elli's accusing words, "maybe you do deserve this." He's taking up Eden's defeatism as an emotional clapback to his own guilt, it's angry and reflexive. He also says:

"I didn't blow up Filament Station, but the ones who did aren't getting pusnihed. I just drew the short straw, and then I traded one fancy metal box to die in for another, while people I thought were my brothers abandoned me!"

Later when pleading with Ava for a rescue, he says:

"I had nothing to do with Filament Station, I swear! That wasn't part of the plan. They didn't listen to me."

Then during the trip back to the SM-8, we hear Ava recounting that "62 others didn't make it out of Filament Station, and no that doesn't include your compatriots."

Another voice right after says "Leave him, we're all dead anyway."

Then TGWTYCW's voice says "You're going to have to kill your own brothers to stop this", claiming they are Simon's words, not his.

Now there's some layers to explore here.

Simon's brothers ditched him at some point during the attack and that's when Simon surrendered. Whether they died or not is a bit up in the air. Ava's words could either mean they weren't in the body count because they escaped, or because they only counted COI members. They assumed they were all going to die because they settled on exploding the station with them inside, or they said this because that's just the mentality of Eden soldiers. Whatever happens, they weren't making it back to Eden.

When Simon says "the ones who did aren't getting punished", it could be a point towards the 'Brothers escaped alive' scoreboard, but Simon could also be talking about the Father and whoever else higher in the command chain decided to blow it up. It could also mean that his brothers got to die in a blazer of glory, thus avoiding any repercussions for their deeds, while he got the "short straw" of going through Convict Realization. The abandonment trauma can have many layers to it.

Simon saying "that wasn't part of the plan", he could have easily been kept out of the loop and the plan was always to blow the station up. However given that the conflict lasted several days, this could have probably been a last ditch effort to grab some pyrrhic victory and Simon was against it.

If we take this route, then the news probably blindsided him and it reflects on the section 3 of the dream sequence. He found out, was paralized by the realization that to stop it from happening, he'd have to kill the people he was closest to. He lost his nerve, and the explosion happened before he could do anything about it.

For how section 1 reflects this, is a bit murky.

Simon feels guilt about all the blood on his hands, especially that of his brothers. This feels like a score for 'Brothers died in Filament' but this could also be that those brothers he knew as a child are metaphorically dead. They are 'dead' to him for having abandoned him, for not listening to him and breaking his trust. It can also be a metaphorical blame, he 'killed' them by not agreeing to the plan and staying by their side. He betrayed them first by faltering and then surrendering.

This is as far as I can push the speculations here, but I hope this was useful insight!

I won't pick apart a possible timeline of events on the fall of Filament Station, but I'll go over my interpretation of things:

Simon was primed for violence by his mother from an early age, something he honed and leaned into as he grew up;

The Butcher moniker was given to him in Eden, possbily by his brothers, not by COI;

He was closest to Second Brother among his peers, and they were both part of the attack on Filament Station;

Second Brother confronted him when Simon was paralized by the plan to destroy the Station, probably during a skirmish;

When bid to "do something", Simon surrendered instead of continuing to attack, and his brothers ditched him instead of joining him or fighting to protect him from arrest;

Being arrested, Simon was unable to stop the plan to destroy the Station;

The fate of his brothers is unknown to him, but he assumes they are dead;

Simon has some very complex feelings about all this, and this are some of them:

He feels betrayed and abandoned by his brothers for not listening or trusting him;

He grieves for his role in Filament Station, and the deaths of his brothers and the station crew;

He resents his brothers and the rest of Eden for giving up and not wanting to fight for survival anymore;