Fanfic / A Mother Goo in a Grimdark World

A Mother Goo in a Grimdark World is a fanfic by TheKitchenCalamity. It is a crossover between Grey Goo (2015) and Warhammer 40,000.

A random human lived and died, and was then reincarnated into the universe of Warhammer 40K as a Mother Goo from Grey Goo. Will the universe drive her insane, or will she eat everything that tries to kill her?

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This fanfic contains examples of:

• Action Girl: While Eien is mostly tasked with serving as a commander far away from the frontlines, she can still personally kick plenty of ass whenever necessary as seen in her assisting in the capture of a Keeper of Secrets.

• The Aloner: A common thread and source of angst for Eien is her struggling to deal with the fact that, thanks to the rabid Fantastic Racism and Evil vs. Evil state of the rest of the Milky Way, she and her children are well and truly alone among the powers of the galaxy. This is somewhat alleviated later on with Sinatra and Ronus, but even then that only goes so far.
• Always a Bigger Fish: At one point, Eien outright sneers at a Keeper of Secrets that the Silent Ones (a.k.a. The Shroud) are far more terrifying than anything the Chaos Gods could ever throw at her.
• Ambiguous Gender Identity: While the fanfic is ostensibly a self-insert, Eien is unsure of what exactly their gender identity was prior to being "isekaied" into the Warhammer 40,000 universe (with her earlier on musing that she finds it hard to adjust to being referred to as a woman). However, the author of the fic and Eien herself In-Universe (along with all of the other characters) refer to her almost explicitly with feminine pronouns.
• Ambiguous Situation:
  • On whether or not the Grey Goo and other respective factions previously existed in the 40K universe or not. As the story goes on, while Eien initially assumed that she and the Goo are completely alien to 40K, she gradually finds herself confronted with evidence that muddies the waters a fair bit.
  • The intelligence of most of Eien's "children" is also a bit of a grey area. While Sinatra and Ronus are clearly both sapient and sentient on par with humans, they are not a good basis for comparison since Ronus was originally a Man of Iron with human-level intellect, and Sinatra is an Artificial Humanoid explicitly intended by Eien to have human-level sapience & sentience. Meanwhile, most of the other Goo consciousnesses simply "sing" to each other and Eien for communication and seem to be on the surface fairly simple-minded, closer to properly trained Attack Animals then "people". Complicating matters is how it's implied that they're less "dumb animals" and more, as purely artificial lifeforms, simply operate under Blue-and-Orange Morality and do not see the need to act otherwise. Additionally, there are also minor asides where the Goo consciousnesses seem to showcase higher thinking, most notably in how some of the "smarter" Goo consciousnesses outright worship Eien as a demigoddess.
• And I Must Scream: The Puppeteer Proteans can take control of organic lifeforms, but in the process leave their consciousness completely self-aware and unable to do anything but watch as the Puppeteer controls their body. Eien outright lampshades how horrifying this is, and how much worse it is that she actually isn't more freaked out about it.
• Anti-Magic: Goo Siphons effectively function as this, as they can transmute Warp energy into Goo mass. This means using any form of Warp sorcery on a Siphon will only make the rest of the Goo even stronger.
• Artificial Family Member: Eien sees all of her creations as her children, and in turn they see her as their mother.
• Artificial Humans: Sinatra is an artificial organic entity created by Eien after she studied the genetic code of the Orks and Aeldari with the goal of creating her own species capable of manipulating warp energy on her terms while still maintaining a connection to the Yggdrasil Network.
• Asshole Victim: Invoked by Eien, who notes that the invasive experiments she is performing to explore Psychic Powers are horrifying and barbaric... but as she is performing said experiments on three captured Drukhari, she feels absolutely no guilt in inflicting upon them just a shred of the hideous agony they themselves have forced upon countless innocent people.
• The Assimilator: Any technology assimilated by her goo will allow Eien to recreate it and even attempt to make it more efficient than the original.

• Berserk Button: Anything that displeases Eien will enrage her children, to the point that the Myrmidons will want to wipe said target from existence.
• Benevolent A.I.: While Eien is technically herself the Brain Uploading of a “real-life” human into the Yggdrasil Network, she more or less considers herself to be an A.I. along with having others treat her as such in the story. Eien is also both the story’s heroine and Big Good.

• Beware the Superman: A recurrent theme in the story is Inquisitor Thrax, Captain Titus and the other members of the Imperial forces being repeatedly terrified by Eien’s exponentially increasing strength and intelligence. Titus himself shudders when contemplating the sheer devastation Eien could unleash if she went up against the forces of the Imperium, with him even noting that calling the inevitable result anything other than “wholesale slaughter” would be downright disingenuous.
• Boldly Coming: Played for Laughs in a non-canon omake set many years after the end of the fanfic's storyline, where some quick thinking by Titus (along with a telepathic "bit of inspiration" from the TTS-Emperor) to convince the Goo to leave an Imperial world leads to him and Eien sleeping together. While both deeply enjoyed themselves, the Imperium's dogmatic Fantastic Racism and Eien's own Properly Paranoid mindset leaves the two of them immensely embarrassed & and feeling quite awkward after the whole situation is over and done with... though that doesn't stop them from eagerly going at it again after resting up for a bit.
• Brain Uploading: How Eien was essentially added to the Yggdrasil Network, having her human consciousness snatched from her life on Earth at the point of death and then being placed as the main governing consciousness of the Pathfinder Project.

• Curious as a Monkey: Due to Sinatra being a goo consciousness who is given an organic body, she ended up becoming quite a curious person due to all sorts of new feelings she is feeling to the point that Eien has to restrain her to prevent her from getting hurt.
• Deader than Dead:
  • The only known way to permanently kill one of the Goo lifeforms is via the Shroud. Otherwise, while their physical forms can certainly be destroyed, their souls simply retreat back into the Yggdrasil Network to await being placed back into another form.
  • More significantly, Eien's Siphons can consume Warp energy and convert it into mass to be integrated into the Yggdrasil Network, which Eien eventually realizes can be used to effectively erase a Warp entity "stuck" in realspace from existence, with her specifically using both her Siphons and the Khalkotauroi to wipe a Greater Daemon of Slannesh from reality.

• Drama-Preserving Handicap: To prevent Eien from simply curbstomping all of her opponents effortlessly, here it's made clear that while her Mother Goo forms can assimilate any form of matter into themselves to create more weapons and attack forms, assimilating either non-metals or non-carbon-based lifeforms are far less efficient in terms of production, helping limit Eien's mass economy (as an example, Word of God has claimed that Eien consuming a tall, healthy tree would only provide enough mass for just the head of a Goblin chassis). Furthermore, her nanites can still be outright destroyed (primarily with extreme heat/cold and/or acid) unless sufficiently protected.
• Eldritch Location: The Yggdrasil Network, which Eien describes as basically being an analogue to the Immaterium for artificial intelligences. Most notably, the Yggdrasil Network is actually in part a physical Pocket Dimension, with Eien being able to store the surplus mass created by her goo here for use elsewhere at another time.
• Enemy Mine: The main plot of the fanfic revolves around the Imperial forces on the planet of Exalus (both those who are the survivors of the crash of the Incorruptus, Inquisitor Thrax's cruiser, and the planet's pre-existing Imperial Guard regiment & associated forces) forming an alliance with Eien against the Chaos, Ork, Aeldari and Drukhari forces on the planet. Later on, a successful armistice between both the Craftworld Aeldari and Necron forces (specifically the latter under the control of Nemesor Anckm'rab) is established with the Imperials and Eien so the latter two can focus on the Orks, Drukhari and Chaos.
• "Eureka!" Moment: After repeatedly struggling to grow her mass economy, the Edge Program gives Eien a plan to finally fix it without resorting to strip-mining the entirety of Exalus: Her proteans can brave the oceans of the planet and consume metallic ores, mineral veins and volcanic vents on the ocean floor. Following this, Eien starts to become far more confident in her abilities, the deployment of Goo forces and the experiments she is performing on the Goo itself.
• Even the Girls Want Her: Maria, a member of the Sisters of Battle's Hospitaler Order, is trying very hard to avoid having impure thoughts about Eien due to the matriarch's rather 'gifted' appearance.

• Evil Versus Evil: The Orks and Chaos forces on Exalus actually spend more time fighting one another than they do the Imperials, Eien and Aeldari.
• Extreme Omnivore: Downplayed; Eien's nanomachine proteans can consume any matter and convert it into mass for use by the Grey Goo, but are most efficient in mass conversion with metals and (to a slightly lesser extent) carbon-based lifeforms. Her Siphons play this trope straighter in that Eien can convert energy into more mass for her "children" to use.

• From a Single Cell: As long as a single nanomachine can survive, Eien — and by extension, the souls of her "children" — cannot be killed.

• Greater-Scope Paragon: An ambiguously canon omake where the Grey Goo always existed in the world of Warhammer 40K reveals that the Pathfinder Project is actually responsible for most of the inhabited worlds in the modern Imperium. To further clarify, when it was exploring the galaxy prior to the Dark Age of Technology and discovered the Milky Way to have been mostly scoured of life thanks to the lingering after-effects of the War in Heaven, ancient humanity re-tasked the Pathfinder Project to serve as a “sower of life”, terraforming countless once-inhabitable planets back into a life-sustaining state.
• Green-Skinned Space Babe: Following the Edge Program's implementation, Eien's default form is that of a gorgeous, curvy young human woman with white hair, silvery-grey skin, grey-blue clothing and glowing blue eyes.
• Heroic Sacrifice: While Eien doesn't remember all of the explicit details, apparently her last act in her pre-40K life was jumping in front of a runaway truck to save two children.
• Horrifying the Horror: The Khalkotauroi are Eien's Elite Units, and are so dangerous that they are capable of making a Keeper of Secrets run in desperation for their life.
• Higher-Tech Species: Humanity of the Grey Goo universe, with Eien early on lampshading how terrifyingly dangerous a lot of their tech really is.
• Humanoid Abomination: Eien is a cluster of humanoid nanomachines with a completely gooey body; after an upgrade she ended up gaining a more solid form along with actual legs and a completely gray skin tone.
• I Know Mortal Kombat: Eien's skill in battle tactics and strategy is largely based around her vestigial memories of her previous life on Earth, where she was apparently a rabid strategy gamer.
• Immortals Fear Death: When Ner'isa is finally captured by Eien, she is terrified to the point of begging the Imperials for help when Eien began using the Siphons to give her a true death.

• Intra-Franchise Crossover: The main Ork forces found across the planet of Exalus are led by Grimgor Ironhide, Azhag the Slaughterer, Grom the Paunch, Wurzzag da Great Green Prophet, and Skarsnik — all of whom are originally from Warhammer Fantasy Battles and have been re-imagined to properly fit into the 40K universe. Various elements from previous 40K editions are also used here, such as the Squats being a recognized abhuman strain under the authority of the Imperium.

• Lighter and Softer: While the fanfic does have its darker moments, it overall doesn't take itself too seriously and is more focused on humor, action and exploration of creative implementations of Goo technology in the world of 40K.

• Mama Bear: Nemesor Anckm'rab's attempt to touch one of the souls of Eien's children causes her to threaten to atomize him and then scatter his ashes across the cosmos.
• Meaningful Name: Eien roughly translates to "eternity" in Japanese.

• Mid-Season Upgrade: The Edge Program functionally serves as this for the Grey Goo, greatly improving the mobility and melee abilities of all gooforms.
• Mind Hive: How the Yggdrasil Network seems to work (at least in part).

• Mythical Motifs: With the exception of the Hunters, the vast majority of the Goo morphs are named after creatures/characters from Classical Mythology.
  • The Myrimdons (Eien's Space Marine-analogues) are named after the soldiers commanded by Achilles during the Trojan War.
  • The Khalkotauroi are named after the Colchis Bulls (specifically in reference to how the Khalkotauroi's Volcano Lasers are based after the Colchis Bulls' fire-breath).
  • The Hecatoncheires are named after the ancient hundred-handed giant sons of Gaea and Ouranos.
• Nice Girl: Sarcasm, short temper and understandable paranoia aside, Eien is a remarkably kind and well-adjusted person who is helping the Imperials on Exalus not just out of Enemy Mine logic, but also out of Chronic Hero Syndrome (even showing pity to the miserable plights of the Aeldari & Necrons). Furthermore, Eien is very protective of and gently maternal towards the numerous Grey Goo lifeforms that make up her children, and ultimately desires to make the galaxy a safer place for them.

• Nothing Is Scarier: The Shroud in a nutshell. Even when only seeing a hologram of the Shroud, a highly skilled Aeldari psyker finds themselves screaming and almost clawing at their eyes over how the Shroud “looks like nothing”.
• Our Souls Are Different: Within the Yggdrasil Network, new goo consciousnesses are constantly generated that develop their own souls and when fully formed become stars that float down from the central 'tree' akin to leaves; when these developed Soul Stars sink into the 'sea' they are actively controlling a morph or frame within the Materium. When Warlock Alune nearly had her soul sucked into a siphon, she glimpsed the network because of that, and has started calling Eien "Ishara Orlosa" (which loosely translates to "Mother of Soul Stars" in the modern Aeldari language).
• Outside-Context Problem: Eien, the Yggdrasil Network and the Grey Goo as a whole all serve as this to the universe of 40K.
• Painting the Medium: When Eien possesses one of her Khalkotauroi to taunt Ner'isa Ur'ces in Low Gothic (a language both Aizaun and El'dathar can't understand), the text depicts the Necron Nemesor and Aeldari Knight of Vaul "hearing" her dialogue as wingdings.
• Poor Communication Kills: If Farseer Zalava had said from the start that the threat lurking below Castle Krakengar is a Greater Daemon of Slaanesh imprisoned within an inactive Blackstone Fortress, Inquisitor Thrax and Eien would have helped instead of going to war because he wanted to drive the humans away from the only safe point they had on the planet.
• Pragmatic Villainy: Due to the fact that he is completely surrounded by enemies and the Warp storm prevents him from calling for backup, Inquisitor Thrax has no problem allying himself with an amiable abominable intelligence to survive. He is also planning to recruit Engineer Tiki so that her talent is not wasted and also to prevent her from being killed on charges of techno-heresy, preventing Eien from recruiting her.

• Puppeteer Parasite: The Puppeteer Protean is a goo created specifically to control the puppets that form the bulk of Eien's new machine army, and are also capable of taking full control of the bodies of organic beings.

• Robot Dog: Hunters are quadrupeds specialized in combat, assassination and infiltration that are hardly ever visibly seen on the battlefield due to their advanced stealth abilities. They also resemble a mechanical version of a wolf-cougar hybrid.
• Shout-Out:
  • The majority of the original Goo combat morphs Eien creates are based upon (and named after) chassis used by the Vex from Destiny (with the Puppeteer Proteans animating the chassis in a similar manner to how the Vex do).
  • Meanwhile, the Khalkotauroi are based on the Mark X Sentinels from X-Men: Days of Future Past, the Hecatoncheires are inspired by the Mimics from Edge of Tomorrow, and the Hunters are designed to resemble Blade Wolf from Metal Gear Rising: Revengeance.
  • According to Eien, the makeshift Powered Armor suits created by Engineer Tiki for the Imperial Guard forces look incredibly similar to the T-60 Power Armor suits from the Fallout series.
  • After undergoing the Edge Program, Eien discovers that her new humanoid form looks quite similar to that of Nikusa from Friday Night Funkin'.
  • Eien specifically notes that she is taking inspiration from the Protoss of Starcraft fame when designing the bio-mechanical head extensions for Sinatra that will allow her to connect to the Yggdrasil Network.

• Stating the Simple Solution: At one point, after she learns her Siphons can devour Warp energy & convert it into mass for the Yggdrasil Network, Eien contemplates simply creating a massive rocket laden with Siphons, launching it into geostationary orbit, and then devouring the Warpstorm surrounding the planet from the inside-out so she can just escape and not get bothered by the Imperials & other forces. However, she then quickly dismisses this option upon realizing that this would take an incredibly long period of time where she would have to be constantly guarding the rocket/satellite from enemy attack, and that if she tried to just speed the process along by having the Siphons create more Mother Goos and protean masses to make even more Siphons, the protean masses would be unprotected when created by the Siphons and would quickly freeze into an inoperable state thanks to the vacuum of space.

• Taught by Experience: One of the many advantages of the Yggdrasil Network is that it effectively grants the Goo consciousnesses with Ressurective Immortality, with then being reborn into new physical forms after their previous deaths. As such, this lets them all become significantly more dangerous over time, as death simply becomes a learning experience and they all gain a better understanding of how to make war.

• Thank the Maker: All of Eien's children revere her as if she were a goddess and call her "the Great Machine Mother".

• Universally Beloved Leader: Eien is universally beloved by all of her children and even Ronus, a Man of Iron, only showed admiration for meeting her and continues to worship her after joining the Yggdrasil Network.
• Weather-Control Machine: Eien has three specialized goo units that, when put together, are capable of creating a lightning storm which she uses to wreak havoc upon the Drukhari.

• World Tree: The respective imagery is invoked with the Yggdrasil Network, which primarily consists of an unspeakably massive tree with stars instead of leaves and from which new Goo consciousnesses are formed (along with partially serving as an interface for Eien to alter said network).
• Worthy Opponent: All of Zalava's interactions with Eien involve him showing enormous respect for her, even comparing her to Isha, the Eldar Goddess of Life and Harvest, and wishes that after the conflict is over they can maintain a friendly relationship.

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