What is the Sierra Madre's Cloud? | Full lore and speculation

The cloud that shrouds the Sierra Madre is an ever present threat in the Dead Money DLC. Where did the cloud come from? Why is it here? What actually is the cloud? I do my best to use the lore to figure out what the cloud could possibly be made of.

RadKing's Discord:

RadKing's Patreon:

[xboxhomie]

a poisonous corrosive cloud? sounds like the perfect ingredient for a refreshing martini…

[tristanseaver]

"It's about learning to let go." (Letting go of poverty. As I transport 36 gold bars back to the Mojave.)

[Sgt_Robo]

What I believe Elijah means by "protecting and preserving" is not entirely literal preservation, but rather, preventing human scavengers from scavenging and scrapping said byildings and relics. That said, the cloud may also perform som preservative function in a way like aluminum oxide, where the corrosion of the cloud only affects the outer layers materials, but paradoxically said reaction creates a protective coating stopping amy further reaction (at least for some materials, others like organic material just corrode into uselessness).

[glaz_man]

I've seen a theory, that cloud made people inside into some weird spongy thing that moves just like spiders do. Citation: "Each leg's outward movement is controlled through the cephalothroax, which regulates the hydraulic movement and pressure hemolymph". The dude who came up with this theory, said that weird twitchy movement of the ghost people is a result of this hydraulic pressure in limbs. The don't activate muscles by nerves how living things do, but spread pressure around the limbs to move. The Dog also said that when he kills ghost people, they make "hisss" sound and stop moving, which signals about pressurized liquid or gas escaping. Crazy theory, but it caught my eye.

[Haru-spicy]

Remember that Big MT already has trauma harnesses that can 'preserve' or at least take over the functions of the wearer's body after death. The darklight suits may yet be an attempt to upgrade the survivability of the suits by subjecting them to seriously deadly conditions such as the Cloud. Given that the ghost people could still 'technically' be considered living, this is at least a partial improvement over the walking skeletons we see in OWB, especially by Big MT's fast and loose standards.

[ryanbusch]

Part of me wonders if the darklight suits contain some parts of what went into the trauma harnesses, like yeah they also appear to have been ghoulified but the way they stand back up after death feels very similar to how the tests for the harnesses were described… and who’s to say that the trauma harnesses wouldn’t take a few more hits if they contained a feral ghoul and not just a skeleton

[bluetoothschizophrenic]

With how crazy a lot of Big MT’s experimentation is, it wouldn’t surprise me if there is a sort of nanobot component to the cloud, which could interact with components within the suits to engage some sort of dormant life support system or create a chemical mix to transform the occupants

[vaultboya]

When you first start the dlc, you're stuck there from beginning to end and you can never go back. I think it makes it super unique and one of a kind. It's a once of a life time experiences that the courier lives through.

[gabriellavedier]

I think the darklight suits were intended to test the penetrative power of the cloud, as the Big MT scientists were egotistical in their work and liked to do horrible things to people in a quest to one-up their colleagues. The metal was chosen to easily corrode and then force an extended stay in the suits. They work as chemical suits, as you see when you find one, but the cloud is a super successful experiment. I also think the darklight portion does more, possible some super low level radiation and other effect that changes how body chemistry works on a small scale and time frame.

There were real human experiments attempting to create ideal antibiotics that would eliminate bacteria in people. But that always included gut flora, which lead to death. So far as I've heard. That might have been yet another Big MT experiment. Cleansing and preserving humans, also attached to additional tech in the suits.

I also always assumed that way down deep, maybe in the area below Sinclair's vault, was The Cloud Machine, with a huge container of cloud juice. The lower levels really have a lot of unnecessary machines and ducts. It seems that delivering the cloud was intentional but maybe the shoddy work made it more easily released, and that's why one egotistical researcher thought to leap to another experiment right away, to one-up the cloud guy.

[corypowercat]

It's amazing how the Big Empty is responsible for everything in the other dlcs. Also the spore people in Vault 22 and in Zion. Also the meaning behind this DLC has helped me a lot with letting go of unhealthy things.

[heiroftheredeemer]

I wouldn't say it's Sinclair's ego that made him create the Sierra Madre. If so, it wasn't a malicious or arrogant ego, but a man who envisioned what he could create with his wealth that could last beyond him.

[SierraMonstera]

I think, in a way, the ghost people are a creation of both latent radiation that spread from the bombs, and the cloud.

[frogmouth]

I like how all the new vegas DLCs connect to eachother. It’s cool and illustrates non linear stories.

However it also has the drawback of making the world seam much smaller.

[amuroray]

The fact that Elijah travelled to all these places without dying is impressive. He was completely insane but he must have been a skilled BoS soldier….Because these guys take aLOT of bullets to put down. And so do the robots in the Big Empty.

[nyekomimi]

Small personal theory of mine is, there are other ghouls in the Sierra Madre... the ghost people mutated to feed off cloud instead of radiation.

[bunibel]

The Sierra Madre was built as a testament to his love for Vera Keyes and to protect them both from the progressing war, Sinclair says this pretty much verbatim in one of his logs, not sure how his ego came into the equation here, he is depicted as an incredibly positive person who tries to see "the bright, shining future in everything" according to Dean, which doesn't mean he is completely selfless but it does paint him in a particularly different light

[Kirhean]

My personal theory is that the red cloud is a type of "smart matter" which can be configured and reconfigured at will by the vending machines. It was stored in pipes and reservoirs beneath the Sierra Madre and when it leaked it was toxic because it was not configured, so it imitates whatever material it integrates into. The tokens are a combination of currency and power source.

[shaynecarter-murray]

Love this channel.
It amazes me that Fallout has so much lore that multiple channels can generate enough good content to actually have traction using games from over a decade ago

[BoredomItself]

When I played the game I always thought the cloud was some kind of simple nanomachine type tech. The cloud particles being the nanomachines themselves, and the gas being some compound, or mix of compounds needed for the production/maintenance of the machines. The residue being the nanomachines having fallen from the air and collected in some place while undergoing some regenerative process. I thought that the reason it never spread outside the area was because it needed some power source or else it would eventually break down, with the gas potentially having some component that was a chemical energy source. The reason for the ghost people being that inside the suits they had something to modify the nanomachines and give it new instructions including repairing the host body, just like how one can craft something from it that will heal you. The reason it destroys some things while preserving others being that it was meant to bypass what people would use to protect themselves, like gas masks, but like other chemical and biological weapons one of the goals is to leave the infrastructure and existing tech intact for capture and repurposing.

[platinumshadow]

Great analysis and you didn't leave anything out. The Cloud has always fascinated me and I see it as a unique work of diabolical chemical engineering, like FEV but its own thing. Inspired by the real world agents you mentioned but its own synthetic design. As you noted, it can be hard to reconcile its corrosive properties with the way Elijah describes it preserving Old World technology. I recently found myself wondering if perhaps the Cloud has a particular chemical reaction with the Saturnite alloy (also developed at Big MT) which could explain why the Cosmic Knives decay from exposure to it. Perhaps the mechanical locks on the Darklight Suits were also manufactured from Saturnite? If that were true, it would mean that, while the Cloud attacks living tissue like a form of necrosis, it leaves inorganic matter alone save for its corrosive chemical reaction with Saturnite. I think that Big MT's experiment with the Cloud at the Sierra Madre was both to observe its effects as a biological agent against the inhabitants (probably to test its use in war) as well as to test their chemical suit prototypes against it and observe the effects of the Cloud leaking into the suits at a much slower rate over time. Elijah's comments about how the Cloud "preserves" seem best understood as veiled references to using it like nerve gas, fumigating places of their living inhabitants while leaving the technology his for the taking. I have also wondered if "Cloud residue" might simply be the remains of organic matter that has been killed and broken down by the Cloud over a long period of time.

There could also be something antagonistic between the Cloud and radiation. Sinclair's automated security systems were careful to screen any traces of radioactivity from admittance into the Casino and Dean, a Ghoul, is both immune to the general toxicity in the air as well as being able to travel through concentrated Cloud much longer before suffering any adverse effects. Dean can even temporarily shield the player from the effects of the concentrated Cloud if traveling with them, which again could imply that radiation is able to protect one against its effects at least temporarily.