In the backstory of Splatoon, everything dies (presumably from oceans rising as the Octos and Inkos fight over territory) Except for molluscs and other sea animals. A cat is cryogenically frozen and revived though.
Minors are recruited to fight against another race of people, but as no death in-game is permanent, and all the action is cartoony, I wouldn’t say it’s abuse. Just one of those things that’s questionable if you think about it too hard.
there are references to foods that contain squid and octopus but nobody is shown eating them, and canonically these are different creatures than the player characters anyway
In Octo Expansion, the main villain kills top-performing Octarians by blending them into an ooze that gets injected into other Octarians to control their minds. The concept itself is very creepy and kind of like body horror in a sense. Octarians change color entirely after being injected by remains of their fellow civilians.
In the backround toward the end octo expansion pack, the player can hear what sounds like screaming or crying. Some people think it's tortured or dying octolings. Nothing on camera, though.
The sanitized Octolings in Octo Expansion are implied to be dead or reanimated. While their ages are left ambiguous, they look similar to the player characters, who are stated to be around 14.
In Octo Expansion, a character is kidnapped offscreen while Agent 8 escapes from the facility they're trapped in. The character is freed right before Agent 8 reaches the surface.
There are two characters who are mind controlled rather than possessed— one in the final boss of the Story Mode that is played when you enter the grate with Marie standing over it, and one as a boss in the Octo Expansion DLC
A bit of almost-fourth wall breaking in Off the Hook’s Splatfest dialogue, and a mention of their world being a simulation in one of the regular stage reveal dialogues.
There is technically no antisemitism, but the optional DLC Octo Expansion features a plot that heavily involves fantasy racism, an attempted mass genocide to make way for a "superior" race, and biological experimentation, which may be reminiscent of the actual Holocaust.
While there's no overt misgendering, this game was released before Nintendo went in the "choose a style" direction instead of "choose a gender," and the options are male and female. However, referral to the player character as any gender is extremely infrequent.
Of the fantastic racism sort. In the ending of Octo Expansion, Telephone/Commander Tartar sees Inklings and Octolings as inferior species in comparison to humans and attempts to completely eradicate them.
There's some racism between Inklings and Octarians/Octolings, but outside of Commander Tartar, not much more is shown than snide remarks from Marie in Octo Canyon, jokes from Pearl on broadcast or Cap'n Cuttlefish pointing out things about Octolings (though he claims he 'doesn't see species' and that he's friendly to anyone who likes the Squid Sisters).
The character customizer available at the beginning of Octo Expansion is close to nudity, as your character is floating in a tube of liquid with no clothes, but the chest and crotch are covered by convient posing and green ink splatters.
whoever made that other comment was bsing, the female ink/octoling model is near identical to the male octoling, spare for a slightly wider hip which you can barely tell the difference because of the clothes the characters wear and the art style.
There is a scene in Octo Expansion where, if the player fails to complete the final boss event in time, the city of Inkopolis is destroyed. This is not the true ending of the game, however.
If a character takes too much damage, they will explode into a puddle of ink. Aside from one color palette available in private battles, there is no red ink in the game, so it doesn't look like blood.
Not an explosion, but if you lose the final boss of the Octo Expansion DLC, Inkopolis is shown to be destroyed in a flash by the main villain of the expansion.