General
- Considering that Inklings are evolved squid, they're generally viewed as laying eggs. Octolings, Jellyfish, and the other species are the same way. Canonically, while nothing as been said about most of these species, the Jellyfish reproduce via asexual reproduction. One Squid Research Lab post also uses the term Paralarvae (the term for the stage of a cephalopod's life between hatchling and subadult), so the theory may not be so farfetched.
- It is commonly believed by fans that the Octolings are the base species for the Octarians as a whole, possessing a sexual reproduction and a development cycle similar to the Inklings while the Octotrooper classes are created from tentacles cut off from Octolings and thus have no reproductive capacity. The official artbook guides don't give a clear answer on whether Octolings are uniquely different from the Octotroopers or if they are just advanced troopers born from cut-off tentacles. One artwork in Inkopolis Walker does seem to indicate an Octoling can be developed from a severed tentacle, but PAUL the 10-year old Octoling DJ looks like an Octoling version of a prepubescent Inkling, Diss-Pair's Octoling DJ Warabi is explicitly stated to have parents (in Inkopolis Walker to boot!), and both developer interviews and the Splatoon Base website have established an explicit distinction between tentacle-type Octarians and Octolings.
- It was assumed by fans throughout the original Splatoon that the characters were much smaller than adult humans. The reveal of character heights in supplementary material of the second game, however, reveals that everyone is to human scale.
- Finn Feeder, the violinist of Bottom Feeders, is female but looks like a male Betta fish. Fan consensus is that she's transgender.
- "Inktolings" are a common subject in fan art, the hybrid offsprings of an Inkling and Octoling. Many fans want this idea to be official canon as it would finalize the unity of Inkling and Octoling community after a century-long feud.
- Likewise is the concept of "Salmonlings", a hypothetical third race of playable creatures based off of the Salmonids from Salmon Run. They're often seen as the most chaotic and rabid of the three, with the greyish skin and mohawk hair of the Salmonid race.
- Agent 3 having scarring or discoloration on half of their face and part of their tentacles/hair because of Commander Tartar's brainwashing is a common headcanon in fanart. As the Captain in Splatoon 3, they actually do have scars, albeit just on the tips of their tentacles.
- Another headcanon is that all the playable agents are canonically female, mainly due to the female versions (the default female Inkling in New Agent 3's case) being featured prominently in promotional material and the developers referring to them as such in interviews. This is seemingly confirmed in the case of the original Agent 3 and Agent 4, as their default appearance in later games is always that of the Splatoon 1 and Splatoon 2 female Inklings respectively (though Gender-Inclusive Writing is naturally still used).
- The four playable Agents (again, typically female) are often given specific characterizations or character traits:
- Agent 3/Captain is typically depicted as the most serious of the four, almost comically so, with some shades of Chunni behavoir.
- Agent 4 is generally a cheerful Bunny-Ears Lawyer with a love of pranking and teasing the other agents; particularly Agent 3, with whom she often as a Vitriolic Best Buds dynamic (with most of the vitriol being on 3's part). She's also often depicted as being rather short compared to the other three.
- Agent 8 is usually a soft-spoken Fish out of Water, whose naivety of the surface is played for cuteness and laughs. She's also typically depicted as the tallest and given the most pronounced curves and bustline of the four, even (and especially) if written as male.
- Neo Agent 3 is often depicted as, fittingly for their game, the most chaotic of the agents, to the point of having an Ambiguous Criminal History. They're also mostly coded as non-binary due to the third game replacing the "Gender" tag with "Style".
- Many fan artists gave Cap'n Cuttlefish's squid form his signature beard, something Splatoon 3 would later confirm he actually has.
- The Smallfry affiliated with the player in Splatoon 3's campaign is often called "Little Buddy" or "Lil' Buddy" after their nickname in the player customization menu, in order to distinguish them from other Smallfries.
- Harmony's off demeanor is sometimes interpreted as her being The Stoner, or being on the autism spectrum. Or even as an autistic stoner.
- It's a somewhat common trend to depict some Inklings keeping Super Sea Snails as pets, even though the game implies that all they are used for is rewards for Splatfests. Likewise, Inklings owning sea slugs (mainly "Sea Bunnies") as pets is very popular.
- There's a common belief that Acht (a.k.a DJ Dedf1sh) and DJ Paul of SashiMori are connected in some form, mainly coming from the fact both wear hats with the same logo (a stylized octopus). The Haikara Walker magazine outright calls attention to this, theorizing the two could either be blood relatives, or simply follow the same brand. The former interpretation is the most popular, with Paul being thought to be Acht's younger brother (and some Japan-only Splatfest dialogue confirms that Marina is at least on good terms with him, which tracks with her being friends with Acht in their youth).
- Inklings and Octolings are known to be weak to water; the common fan belief is that they're specifically weak to the osmotic pressure from being covered by a heavy amount of it. So getting submerged is lethal, but smaller quantities of water — like getting splashed with light rain — wouldn't hurt them.
Squid Sisters
- It's implied that Callie and Marie were 17-18 during the events of the first game, but most interpret them as having already been in their early 20s instead.
- More than a few fan works portrayed Callie and Marie as adopted siblings due to the fact they're biologically cousins, yet their idol duo is called "Squid Sisters" in the English localization. This is usually in conjunction with them being raised by their grandfather. This was jossed in Squid Sisters Stories, as Marie visits her folks in Chapter 5. Callie also has a chance of mentioning her own parents when spoken to after completing Splatoon 2's Hero Mode.
- Because Callie and Marie are the only idols without a confirmed full name in Japanese or English, fans have had to come up with their own family names for them. The most common names given to the two are "Calamari" (after Calamari County where they grew up) and "Cuttlefish" (from their grandpa Craig).
Off the Hook
- Most fans agree that Marina and Pearl live together, and this is often in conjunction with them also being a couple, based on the romantic undertones in some of Marina's dialogue; especially in Japanese, where she more regularly shows admiration towards Pearl and her official character biography describes her as a "maiden in love". While nothing official has been said on their relationship, the interview included with the Japanese Octotune soundtrack jossed the roommates theory and Marina mentions having a landlord in the North American version of Splatoon 2, though it's implied Marina regularly stays at Pearl's house regardless. One throwaway line in Side Order, where Pearl mentions parking a private jet in "our" backyard when talking about an umbrella she and Marina forgot about does imply they may have moved in together at some point.
- Before the Octo Expansion, Western fans generally assumed that everyone knew Marina was an Octoling and that (most) didn't care. In canon, few people outside of the New Squidbeak Splatoon are familiar enough with Octarians to recognize that she was one, and so think that she is an "exotic" looking Inkling.note This even extended to Pearl in the original Japanese; the English localization didn't get that memo, and so Pearl had already alluded to knowing on multiple occasions before that point. The team's fix for this was for Pearl to make Marina's ex-military status the real surprise for her, while she already knew Marina as an Octoling, but didn't know how to broach the subject. A fair number of Western fic writers would end up running with the idea of Pearl being a Secret Secret-Keeper as a result.
- Pearl's short height, immature personality, and unusual design (including a single pointed tooth, only seen in prepubescent Inklings) initially caused a lot of fans to theorize that she was Younger Than They Look. This was eventually jossed when she was given a canon age of 21, pinning her as the older between the Off the Hook duo. Pearl's height is intended as a reference to the Northern Pygmy Squid.
- Pearl as a Sir Swears-a-Lot due to her tough personality and her career as a rapper. In an odd turn of events for a Nintendo game, the Octo Expansion confirmed this by introducing one of her old songs before she and Marina formed Off the Hook, "#$@%* Dudes Be #$@%* Sleepin". The song is a fast-paced heavy metal Cluster F-Bomb, with a prolonged Sound-Effect Bleep on top of it all. The hidden bonus track on one of the soundtracks also has Pearl seemingly swearing after flubbing a recording.
- As Pearl's full name is only revealed in the original Japanese (where she is Hime Houzuki), fanon has taken to using Houzuki as her last name in English as well. Splatoon 3: Side Order later confirms that Pearl's last name is indeed Houzuki.
- SashiMori's backstory makes mention of them previously being a death metal group, before ousting their tyrannical lead singer and eventually replacing them with DJ PAUL. Given Pearl's personality, history as a death metal vocalist, and it being stated that one band member's shell was a asset in dealing with their singer's harsh vocals, it is assumed their old leader was Pearl. One developer interview, when asked this question, only answered with it being up to our imagination if it's true or not.
- Marina is seen as having a Dark and Troubled Past as a high ranking ex-soldier for the Octarian army who escaped to the surface. Canon would later confirm that while she was part of the army, she was an engineer rather than a soldier. Fanon also depicts Marina as having grown up poor, in contrast to her wealthy best friend Pearl and as part of the wider fanon of Octolings living in destitute conditions in comparison to the more carefree Inklings.
- Marina as bilingual and speaking with an accent. This comes from the Japanese version, where her speech is occasionally rendered in katakana, which is used by other Octarian characters to indicate that they are speaking a different language. Her ordinary speech is only partially rendered this way, implying an accent of some sort, while her lyrics in Off the Hook's music are entirely in katakana, which indicates that she's singing in Octarian. Likewise, her speech in the Japanese version is often overly formal, and she tends to make many malapropisms, further indicating that she's only recently learned the Inkling language; Western fans drop that latter bit unless writing about when she first came to the surface though, sticking to just making her overly polite.
- Early on, Marina was theorized to be directly related to DJ Octavio, as the two are both Octarian DJs and were the only named Octarian characters in the series for quite some time. In canon, while Marina was a high-ranking officer serving under Octavio, her backstory makes no mention of any relation to him. Furthermore, DJing doesn't seem to be all that uncommon among Octarians, as we later saw in artists like Dedf1sh, SashiMori's Paul, and Diss-Pair's Mashup.
- To reconcile her Japanese and international personalities, many Western fans decided Marina was a Shrinking Violet who only acted sarcastic and sassy while on-air to compensate for how nervous she really felt as an Octoling integrating into Inkling society. The Octo Expansion would go on to confirm that this is almost exactly the case.
- Many fans depict Pearl and Marina joining the New Squidbeak Splatoon following the events of Octo Expansion, serving as Agents 5 and 6, to the point that it is often mistaken to be canon. Canonically, the duo were just heroic bystanders that helped save Eight and Cap'n Cuttlefish, though promotional material
and Splatfest dialogue confirms they at least became close friends with the rest of the group as a result of the experience.
Deep Cut
- Although officially confirmed to be female, Shiver is often depicted by fans as being an assigned-female-at-birth non-binary Octoling who uses both she/her and they/them pronouns. This is due to early promotional material for Deep Cut always referring to Shiver with gender-neutral pronouns in every language before she was confirmed female, people misinterpreting her Sarashi as a binder and people liking the idea of the gender ratio for the group being Male/Female/Non-Binary.
- If Frye and Shiver are getting shipped together, expect to see Big Man as the duo's biggest Shipper on Deck, if he's not part of the pairing as a Polycule.
- A common situation for Big Man to end up in within fan works is for him to collapse face down on the floor, whether it be due to sadness, an accident, or just for the sake of it. This is due to the flatness of his body causing fans to call him a "sea pancake", and they end up taking this to its logical extreme. In Splatoon 3 itself, this almost happens at the end of his boss fight, but he holds his body up with his fins before he can collapse completely.
- In the official site's interview with Deep Cut, Big Man claims to be a fan of "this one DJ from Inkopolis." Although this could refer to a number of characters, such as SashiMori's Paul or Diss-Pair's Mashup, fans generally assume this is referring to Marina, who is the most significant character of that description by far. This may have been confirmed by the 2024 Deep Cut concert, where Big Man finally gets a chance to sing alongside Marina. The lore surrounding the Splatfest song "Suffer No Fools" also involves Big Man being left star-struck when he hears Off the Hook is planning a concert in Splatsville, further hinting that the "DJ from Inkopolis" is Marina.
- As of the Wealth vs Fame vs Love Splatfest, it's common to read Frye as a Sad Clown of sorts, who remains chipper on the surface but barely hiding that the repeated Splatfest losses are getting to her. It doesn't help that her chipper attitude in thanking her teams has become a lot more subdued since the Shiver vs Frye vs Big Man Splatfest.
- It's also very common to assume that Big Man is the Only Sane Man of the group, or at the very least the smartest of the three, often characterised as Deep Cut "sharing a braincell, and Big Man has it most of the time". Stage banter during the Splatcast seems to confirm this, such as him once teaching the other two to cook properly (and stopping Frye from just adding bags of sugar to every recipe).
- Shiver's preferred weapon class is often seen by fans to be Splatanas, since she has a Japanese aesthetic to suit the sword-like nature of that class. The game actually points to her being a Stringer main, since she talks about using them in stage rotation dialogue and has Stringers (not Splatanas) in her Tableturf deck. This continues in the Side Order DLC, where the preset weapon loadout based on Shiver uses the Tri-Stringer as its main weapon. The Deep Cut member that actually prefers Splatana is Frye.
- A fan theory regarding Frye's often mentioned little brother is that he's actually Baker, the inkling bassist of C-Side. While Baker's tweets in the Splatune 3 booklet has him describe Deep Cut as strangers, there's not much evidence to suggest this is either true or untrue.
Side Order
- Fanart and fanfiction of the ride up the Spire of Order frequently takes the Ship Tease-heavy banter of the game and ratchets it up, depicting Pearl and Marina as Make-Out Kids who can't keep their hands off each other between floors (whether Pearl is in her drone form or not). This is usually accompanied by consternation from awkward third-wheels Acht and Eight.
- The Parallel Canon boss fight is implied to be a result of Smollusk getting hold of Marina's data on Agent 4 as her security chief. However, fan creations often depict the main Inkling in that boss as actually being Agent 4 themself, Brainwashed and Crazy in a similar manner to the Sanitized Agent 3 fight from Splatoon 2.
