Notice the moon in the background of some promotional posters? It's the final boss.
Here's one for the entire series: In Dead Space 1, the name "Dead Space" was named for the Marker's field of power and the whole zombie apocalypse. Same thing with Dead Space 2. In Dead Space 3, it means that space is literally dead. Dozens of civilizations have been destroyed by Convergence and humanity is just the next one in the cycle of an endless graveyard. Cleverly noted by Serrano.
During the Nexus boss fight, you are Swallowed Whole, and enter what appears to be a digestive system. No other have needed those, so why does this one. However, it's a case of Square/Cube Lawandforeshadowing. Smaller human-sized Necromorphs can get away with having no dedicated organ systems, while city-sized ones like Nexuses need them to survive, like how cutting a simple starfish's arm off will be an impairment while doing the same to a human will kill them. When you kill the Moon, you do so by literally ripping its organs out in its "head" region, so if much smaller ones need organs to live, of course a moon-sized one needs them. Hence, the thing is probably, actually dead.
The revelations of the true nature of Markers and Necromorphs actually go some way toward explaining the Continuity Snarl between the first and second games:
"Make Us Whole" is actually a psychic plea from the incomplete Brethren Moon, if not a general impulse from Red Markers to coax psychically vulnerable people to succumbing to the infection and becoming first Necromorphs and then a Brethren Moon.
It's possible for a person to fight against the mental influence of a Marker, as shown in the end of the second game. Plus, different people are affected by the Marker's psychic emanations in different ways.
Furthermore, it's possible for a Marker to be negatively affected; EarthGov has some kind of shielding that blocks the Markers from spreading Necromorphs until it gets destroyed. We also learned that the Sovereign Colonies Armed Forces are responsible for the Marker on Aegis VII.
What does this mean? It was the S.C.A.F who created the Red Marker's "pedestal" on Aegis VII as an experiment to try and block the carrier waves once they started realising the Necromorphs were being created by the Marker's presence. During the first game, Isaac misinterprets the Marker's pleas to "make us whole" as an exhortation to take the Marker back down to Aegis VII and restore it to the pedestal; aided by the part of his mind that is actually fighting back against the suicidal dementia that the Markers try to induce.
In Dead Space 2, the game's conclusion has the beginning of "convergence", wherein all necromorphs in the close vicinity of the marker suddenly hurtle upwards inexplicably. In 3, it's revealed that full convergence, which happened previously for the "Rosetta" aliens, causes all organic matter near giant markers to fly upwards so a giant "brother moon" necromorph can be created by merging them, allowing for the further spread of markers and necromorphs.
Okay, Isaac's mission is to turn off the Machine, because he thinks it will stop the Markers and the necromorph infestation once and for all. He's wrong, and is actually unwittingly doing the Big Bad's bidding all along. But why do these hordes of necromorphs try their hardest to kill him along the way, especially since they're supposed to form some kind of Hive Mind? Because Isaac full well knows that the Markers are capable of manipulating people, so if he didn't face any resistance on the way, it would be a pretty big giveaway that something's off. However, the necromorph entity should also be very aware by now that Isaac is very capable in killing them, likely bar none. So it's sending its minions in Isaac's way to keep his mind occupied - and is actually counting on that he can survive anything it throws at him, making the whole plan a big Batman Gambit.
The first text log you find is about Isaac getting Ellie a new eye. In Dead Space 2, when Ellie loses her eye to Stross, Ellie shouts at Isaac "You own me an eye, you bastard!". Looks like he remembered.
There's actually a good in-verse reason why horror is (relatively) less of a focus in Dead Space 3: by this point, Isaac in particular has had considerable experience in dealing with the Necromorphs and Markers. He knows his enemy and that in itself dilutes some of the initial terror.
How many Brother Moons are there? How many planets are safe? Abso-FUCKING-lutely NONE!!!
One Brethren Moon = 1 civilization. There are dozens of Brethren Moons out there. So many civilizations succumbed to the Markers and Necromorphs, and humanity was, and probably still is, sitting with its head on the chopping block.
Its not over. Isaac killed only one moon. And he was nearly killed because of it.
Even if the Necromorph threat is completely eliminated, it won't reverse the Unitology takeover. While we see very little of it, it's stated that EarthGov is effectively gone, the military has been eradicated (well besides for one battalion, but that's only 300-1,200 people), and the Unitologists have no interest in establishing order when there's convergence right around the corner. They're well beyond fanatic enough that the end of the Brethren Moons wouldn't stop them; at best, they would disbelieve any assertion that there are no more markers to worship, and at worse, they would get worse while fervently denying it. All Ellie is heading home to in the end is civil war, at best.
And the markers aren't even completely eliminated, so she has to worry about that, too.
Also, don't forget that Danik mentioned that there for every major EarthGov colony and outpost, there is a Marker research facility. Since the Unitologists managed to effectively takeover all of human space, they most likely release the all the Markers they can get their hands on. And judging by how quickly the Necromorphs managed to overrun the Ishimura and the Sprawl. It is reasonable to assume that by the time Isaac managed to defeat Brethren Moon, a significant portion of the human race has already been wiped out.
This one may not be quite so bad: the Brethren Moon over Tau Volantis was the source of the Markers' control signal, and after Isaac and Carver took it out, the signal has stopped. Recall that a text log in Dead Space 2 explicitly said if that happens, all Necromorphs melt into a puddle of goo. Now, of course, we just need to hope that another Brethren Moon doesn't restart the signal to the Markers in human-colonized space...
Aaaaaand the Awakened DLC shows us that the other Moons made it to Earth and the slaughter has just begun. Oh Crap.
Related to the above; Scientology's reputation took a considerable, well-deserved, likely permanent dive when the cult as a whole just couldn't handle being exposed on the Internet, from Xenu to Tom Cruise redefining "batshit crazy" everywhere he goes to the controversial deaths of some members to their failed attempts at infiltrating the United States government. Dead Space 3 gives us a look at what could happen if such an organization was run by people who could actually get things done.
A somewhat minor example exists in the Arctic Survival Suit that Issac needs on Tau Volantis; a briefing tape states that, due to the extreme cold and the potential for liquids to compromise warmth, all users must wear a catheter and colostomy contained in the suit to gather urine and faeces in case of being trapped in the cold. Considering Issac is in the cold for several hours and the machine that changes his suit pins him down and works automatically around him, it can have unintended implications.
Brother Moons are horrible monsters that destroy entire planets for survival, selfishly consuming it for the fauna before it moves on. Nothing like the humans, who use planet crackers to destroy planets for survival, selfishly consuming it for the resources before they move on. However, the fact that the Brother Moons knowingly eat sentient beings makes them worse.
The first letters of the chapters spell out a message again. This time it's "BROTHER MOONS ARE AWAKE." So even if Isaac and Carver defeated the Tau Volentis moon, the other ones might still be alive.
Awakened DLC: THEY MOST DEFINITELY ARE!
And the Awakened DLC's chapter titles? They spell out RIP.
The Feeders are people who, to avoid starving, ate necromorph flesh. They are the only Necromorphs that have been observed to be eating, and they die if you shoot them in the head (while all the other forms simply keep going headless). The reason of these anomalies could be that they are not dead.
Made even worse later on in a Video Log that clearly displays that a Feeder's necromorph transformation is a mental one (The Feeders heard in the background of that log can still talk and speak with cannibal intentions), not a physical one and in another Video log the same soldier mentions that some of feeders attacking one of the bases were his former colleagues and that they showed signs of recognition upon seeing him. The Feeders regonized their colleague and attacked him with the sole intent to eat him alive alongside other necromorphs that likely would tear him apart. They are truly driven mad with hunger...
In the bio lab you can find various trench coats and empty hazmat suits laying around, no bodies or necromorphs near them. After you turn the corrosive gas on to destroy the necrotic flesh blocking the doorway, you realize that the suits might be empty because the people inside them melted during an accident. Isaac can be killed by it, too.
The Awakened DLC ends with Earth being surrounded by Brethren Moons. Now... where was Ellie last seen heading at the end of the vanilla game?
Look around Isaacs room at the beginning of the game. Its filthy and cluttered, and an audio log seems to imply he doesn't have much too live for. Was he planning suicide?
Our current (USA) military personnel is around 1,138,044 people. There is ONE battalion left in Dead Space. That's 300-1,200 personnel. Considering all the many colonies AND territories that governemnt is in charge of AND the fact that the Earth is now unified under one banner, what in God's name killed 2 to 3 MILLION soldiers. How many Unitologists are there that killing that many people is possible? Given the religious freedom that people still have, we have to assume many of those Unitologists WERE part of the military and were killing their comrades and now a Brethren Moon is releasing hell directly onto Earth... which now missing a military presence besides for a single battalion and, potentially, hundreds of thousands Unitologist fanatics who may not even bother to fight the monsters given what they believe in.
Their is no indication if the Brother Moons are an actual species (I regard it as unlikely as they're entirely made out of dead tissue from a convergence event). So...what if they were created by something MUCH worse? Think about it...what kind of aliens would create the Brother Moons? They are completely made out of necrotic tissues, are capable of speech and causing entire civilizations to go mad for CENTURIES, and just eat and eat in till their is nothing left of an entire galactic empire of that very species. Look at the Brother Moon's at the end of the DLC, they do not want to create another moon, they want to destroy humanity and other species around the galaxy by devouring them...
Why exactly did Isaac ask to pilot the shuttle down to Tau Volantis? He knows full well that Ellie is a certified CEC pilot who saved his life with her skills in Dead Space 2, and he ends up having to put out engine fires and generally act as his actual job in addition to his piloting. It would make a lot more sense for him to have Ellie fly the shuttle and do just his own job, rather than doing both which ended up being Lethally Stupid for Rosen and Locke.
That and Ellie is a heavy equipment pilot, means she can drive giant drills, doesn't means she can drive 200 year old spacecraft well.
However, said pilot would have a better chance at flying it than the engineer, since she demonstrated she can at least fly gunships well.
Correction; the Merchant Marine Engineer who flies a shuttle at the end of both DS 1 and 2. Ellie was co-piloting, and took over when Isaac went to the rear. It was a centuries-old ship that absolutely none of them were technically qualified on. Rosen, the team's "official" pilot, was injured, and Locke apparently didn't feel like doing it herself. And since Isaac is basically the team leader at this point, everyone deferred to him.
It's possible that he didn't want to put her in harm's way with a ship barreling down nose first through the atmosphere of a planet. Look at what happened to the navigator behind Isaac, he got half of his head sliced off by debris. Being an engineer, he probably realized this and took the helm.
Isaac's ability to orient himself to the ground while flying is handwaved as his boots having built-in electromagnets. Which worked fine in Dead Space 2 and most of Dead Space 3. However, in the final segment, he can perform this maneuver within the Machine...where the ground is made of rock, not sheet-metal plating like the various spacecraft.
Highly metallic ore?
Isaac nearly dies after crash landing on Tau Volantis because of damage to his helmet exposing him to the freezing temperatures of the planet. Isaac tears off his helmet for the final boss fight and experiences no ill effects for it, despite said battle looking to take place in the same planet's even colder upper atmosphere.
It's stated in extra content that the violent explosion of blood we see happening when corpses are converted to necromorphs is due to the cells' metabolism being sent into hyperspeed and literally boiling blood and other fluids by the generated heat. The Moon is currently absorbing all the material of Tau Volantis, so ironically the death of the planet may be saving Isaac. Also, Isaac is literally inside the mouth of the monster, which could insulate from the cold atmosphere.
For that matter, during the initial crash, only Isaac's helmet is damaged. Carver's helmet is just fine, yet he also continues to lose body heat at the same rate Isaac does. Say what?
The out-of-universe explanation is that the second player needed to have a similar handicap to the first, because then even more people would be complaining. For an in-universe explanation, perhaps the suit need a firmware update (provided automtically with the first suit recieved on Tau Volantis and applied retroactively) to apply the proper insulation routines, like only opening air vents with inhalations/exhalations and powering heating mechanisms.
Of all the named characters, only Isaac and Carver wear RIGs or the attached equipment such as Kinesis and Stasis modules. For characters who are experienced spacers who at the very start of the game narrowly avoid death because of their ship being damaged to the point of decompression, you'd think that they would make an effort to suit up and massively increase their survival chances. It's a miracle that Austin Buckell survived as long as they did on Tau's surface, and if ONE of the party with him had a Kinesis module (and unless if you're playing Co-Op, there will be one) they could have fired up the nearby generator and saved his life before hypothermia killed them.
The said character clearly has severe hypothermia, which results in body temperature dropping so low the organs and brain begin shutting down unless professional medical intervention is found. Increasing the head might make them more uncomfortable, and even potentially worsen them by exposing them to heat so suddenly (or failing that, maybe the generator cut out due to lack of maintenance in 200 years).
Why would a crew of ostensibly intelligent people would look down on a planet with a frozen biome and fail to consider finding some sub-zero environment suits in the ship graveyard before descending. It's incredibly unlikely that they wouldn't have a spare suit or two knocking around in one of the ships.
Somewhat justified in that, before leaving, a character mentions that the repairs have luckily matched up with their brief flight window. Considering the amount of damage and deaths they suffer by landing during the most ideal time window, looking for suits would have meant certain death.
Why didn't the team promptly search for RIGs upon arrival, or before arrival seeing as the USM Eudora apparently had a full stock of vacuum-safe RIG suits?
Save for the single emergency suit Issac finds on Norton's ship, all suits are only stocked and fitted by the RIG stores, and would require everyone walking through danger to be fitted with their own suit in store; when you're heavily injured and there's monsters everywhere, it's understandable they overlooked it by prioritizing getting to a safe place or building a shuttle. Additionally, Norton demanded right until launch that they weren't going to Tau Volantis, and getting a suit would mean a) disobeying a direct order from an asshole superior when he wasn't in the best mood, b) counting on them having the right sizes and enough in stock at that specific store, and c) then walking through certain death with no supplies and few weapons all to get a suit before they knew for certain if you were heading down to Tau Volantis or going home by Norton's command.
Isn't it physically impossible for orbital debris to hang that densely for two hundred years without deteriorating? I thought this was meant to be relatively hard Sci-Fi, not WALL•E.
Outside of the science surrounding the local Applied Phlebotinum (The Markers, Necromorphosis) and scientific disciplines (Planet Cracking, Sparklight FTL), the series is relatively consistent in retaining the Willing Suspension of Disbelief. That said, Tau Volantis is explicitly an Eldritch Location; strange phenomena surrounding it can be given a Hand Wave by virtue of proximity to The Machine and the Brethren Moon
That and Tau Volantis is located in the HR 8799 system, which, from current observations has a extremely large asteroid belt/field(Reference:Dead Space 3 Prima Guide).
The basic RIG suits Isaac uses to space-walk are designed to survive the deep cold of space AND intense heat caused by solar radiation. A modern space suit will keep you alive in Antarctica just as surely as it would in upper orbit; why would it be necessary to switch out for an specialist suit anyway? That, and the only reason the EVA Suit (or any other suit for that matter - even the Arctic Survival) fails to protect Isaac from the cold is because of the helmet malfunction. If you "repair" it at the Suit Kiosk, it still protects you from the cold, like any other suit. The mission log even notes this directly.
Space Does Not Work That Way. Even in deep space, where the temperature is in fact very low, it's still not "cold" in the usual sense — you won't lose heat very quickly, because vacuum is a very good insulator, and even if the suits were insulated against low space temperature, it doesn't change the fact that we're talking two totally different environments and two totally different suits (i.e. one will prioritize oxygen insulation and the other heat insulation).
The opening of the game indicates that, after the Sprawl incident, Ellie wants to go Marker hunting to try to destroy them, and dumped Isaac because he refused to follow her. However, why is it that, while being on and seeming to think herself to be borderline in charge of a team on the way to and staying on Tau Volantis, she never bothers to actually carry a weapon with her to defend herself from the Necromorphs she is sure to encounter when hunting them down to try to destroy them once and for all? Considering her expertise in 2, joining a group of EarthGovSpace Marines (the very group that she basically invaded in the second game with a giant drill) essentially to be protected by them instead of working alongside them in combat seems rather nonsensical, bordering on Genre Blindness.
Norton is overprotective. He probably suggested for her to stay far, far away from anything that could hurt her. Plus she could have lost any weapon she had during the crash on the planet. It's not like she an engineer that can make a weapon out of duct tape and spare parts like Isaac can.
In the Awakened DLC, Carver does try to contact EarthGov Command in the ending so EarthGov may not be completely gone yet. Plus, there is an entire battalion left. You think Norton would say there's still a battalion left when there's only, like five of them looking for Isaac? That would be Earth's last squad, not battalion. A battalion includes anywhere from 300 to 1,200 people.
Its possible that the rest of the battalion was holding off a larger fraction Unitologists allowing the small squad to sneak around and get Isaac and flee.
In what universe is tungsten rarer than the active ingredient in a Healing Potion? (Seriously, that Somaticgel drops like rain in the Amazon). At least it explains why this series is so damn dark all the time: no one in this setting has ever heard of a light bulb.
It's explicitly stated throughout the franchise that humanity doesn't have enough resources to go around anymore. The somatic gel is a chemical that would be easy to mass-produce, but tungsten is a natural material, so it's probably really hard to get any large amount of it.