Nintendo's Splatoon is a fun little game about squids shooting ink at each other in friendly competition, and that's it, right? While it might seem like that on the surface, it couldn't be farther from the truth. A deeper understanding of Splatoon's backstory and lore quickly betrays the cutesy aesthetic to reveal hints about human extinction, nuclear war, and immortal psychic cats.
The thing about Splatoon's lore is that it doesn't reveal itself easily: many of the most interesting tidbits are revealed in hidden items called Sunken Sea Scrolls that can be uncovered in the single-player modes of both games. Going deeper still, some secrets are uncovered in developer interviews and untranslated artbooks, which often contain some of the Splatoon universe's most unknown facts.
Splatoon Is Set In The Post-Apocalypse
Yes, that's right, the family-friendly Nintendo shooter about funny-looking squid is in fact set approximately 12,000 years after an extinction event wiped out the human race. The extinction event in question most likely had something to do with rising sea levels, as Sunken Scroll 10 from Splatoon explains that the "Mollusk Era" began when the ancestors of the Inklings crawled onto the surface.
Other sunken scrolls from Splatoon depict fossilized human skeletons, and in Splatoon 2 Marina will occasionally refer to uncovering human bones in news segments. Human extinction being explicitly canon is pretty unusual for a Nintendo game, and knowing this adds a weird surreal element to the game's setting.
Judd Is Immortal
Certain sunken scrolls in Splatoon show images of a cat that appears to be Judd during the Great Turf War, approximately 100 years before the start of the game, while others show a hieroglyphic carving of a cat that appears to be Judd from presumably thousands of years before the events of Splatoon. But could that really be the same cat?
Yes, that's the same cat. Sunken scrolls 25 and 26 in Splatoon reveal that a certain professor not only sealed Judd away in a cryogenic capsule, but also injected him with some sort of immortality drug. This explains why Judd is the only surviving land creature to be found in Splatoon, and why he's in sunken scrolls from so long ago.
Splatfest Results Determine Actual Laws
At the end of Splatoon 2's ice cream versus cake Splatfest, Marina tells Pearl that since ice cream ended up winning, ice cream is now "legally better" than cake. Initially, it might seem like she's joking, but when Marina tries to protest the results of a later Splatfest (chicken versus egg), Pearl immediately declares her to be in open violation of article 3 section 2 of Splatfest law.
This can only mean that Splatfests really are that important to the legal structure of Inkling society, and it explains why they are taken so seriously by seemingly everyone involved. Fans have also speculated that the seemingly post-apocalyptic aesthetic of Splatoon 3 is a result of Team Chaos's victory in the Final Splatfest of Splatoon 2, which would make sense given what we know of Splatfest law.
Commander Tartar May Have Been Created By Judd's Owner
The ancient A.I. with genocidal ambitions, Commander Tartar, is the ultimate antagonist of Splatoon 2's Octo Expansion. The fact that a machine intelligence has been melting down test subjects to reconstitute the ultimate life form is strange enough, but the fact that the entirety of Inkopolis will be annihilated if Agent 8 fails to stop him makes things even weirder.
Commander Tartar also refers to his creator: a certain professor, as one who wanted to preserve the culture of humanity. We already know of one professor with a penchant for preserving things from the old world, and that's Judd's owner! Did he ever intend for Tartar to try to eliminate the Inklings, or was this all a simple case of A.I. run amok?
Jellyfish Share A Hive Mind
Splatoon's Jellyfish can be seen ambiently wandering around many of the game's environments, such as Inkopolis square or the various multiplayer stages. They all appear to be engaged in fairly normal activities, like running shops, hanging out, and exercising, but the cognition of these creatures is apparently quite different from how it might seem.
Splatoon producer Hisashi Nogami has suggested in an interview that jellyfish are not in fact individuals, but part of some kind of superorganism with a shared cognition. This means that jellyfish that appear to be independent are in fact just instances of the hive mind mimicking how an individual might act.
The World Of Splatoon Is Facing A Climate Crisis
Splatoon fans are generally aware that the situation facing the Octarians (the longtime enemies of the Inklings) after the Great Turf War is rather dire. After losing their territory to the Inklings they were forced to live underground, and constant power crises drive them to steal zapfish from the Inklings to keep the lights on.
But what instigated the Great Turf War in the first place? Sunken scroll 16 in Splatoon reveals that relations between the two species were amicable until rising sea levels forced them into a conflict over territory. While it's unclear exactly what caused sea levels to rise, the situation is eerily familiar to the climate change that brought about humanity's extinction more than 12,000 years ago.
What Do Inklings Eat?
Sunken scroll 21 in Splatoon displays an image of a fried prawn, with the accompanying text seeming horrified that the ancestors of the Inklings might have eaten something that looks so much like the prawns of Splatoon's present day.
However, in Splatoon 2, Inkopolis's resident prawn has opened a food truck called the Crust Bucket that sells food items that look disturbingly similar to the fried prawn depicted in sunken scroll 21 (you can even see claws poking out of the galactic seanwich). Could Crusty Sean be deep-frying his own kind to corner the Inkopolis lunch market?
Ark Polaris Is A Failed Human Generation Ship
The Salmon Run map "Ruins of Ark Polaris" has some pretty interesting imagery that makes it stand out from others in Splatoon 2. In the background it's possible to see the ruins of what appears to be the engine block of a space shuttle, as well as a crashed satellite. One of the wings of the "space shuttle" has the faded text "ICA" and "Private Property" on it, notably written in English rather than the squid language we see in the rest of the game.
We know that the vessel is of human origin, and we know about what happened to humanity in Splatoon's lore, so the use of the term "ark" suggests that Polaris was likely a vessel intended to ferry human survivors to a new home among the stars. Clearly, this didn't pan out, which raises the question as to what happened to the Ark, and whether there are other ships like it.
Salmonids Are Sentient
While they might appear to be simple barbarians, Salmonids apparently have a complex warrior-oriented society that simply isn't shown to the player. Sunken scroll 19 in Splatoon 2 reveals that they are dedicated to maintaining their weapons and that the simple frying pans carried by the hordes are often family heirlooms passed down through generations of Salmonid warriors.
This raises some questions as to what exactly the player's relationship will be to the miniature Salmonid buddy in Splatoon 3 will be. While he at first appears to be a simple pet that follows the player around, a deeper understanding of Salmonid culture might mean there's more than meets the eye when it comes to this lil' buddy.
World War 5
While conventional wisdom suggests that humanity was wiped out due to rising sea levels, a "kinda serious" Splatoon backstory comic from the Japanese artbook Haikara Walker suggests that the real causes of the apocalypse may be more complex than simple climate change.
The comic refers to humanity fighting "five great world wars", and also depicts a nuclear weapon being fired at the South Pole, which may have contributed to global sea-level rise. It's unclear exactly how canon this comic is supposed to be given that it only appears in a single artbook, but Splatoon certainly has a penchant for weird, dark backstories, so nuclear war doesn't sound too crazy at this point.