The newly appointed Captain of the New! Squidbeak Splatoon. 26 years old. She has blue eyes and fair skin. Her gear consists of a fluorescent vest over a black hoodie with a cape, but her Captain's outfit is Cuttlefish's old tattered clothes, captain's hat, and sandals. An Inkling woman from Inkopolis. She formerly served as Agent 3 and led numerous operations. Her aim is incredibly sharp. She is quiet but looks out for others from behind the scenes. She is blunt. Lately, she says her back feels stiff due to age. She has a soft spot for Agent 8. She smells because she doesn't wash often; Agent 8 has to drag her to the hot springs to get her to clean up. In truth, she is very kind and treats people well. She has long orange hair with scars on her large hair tentacles. Her main weapon is the Hero Shot.

An Inkling woman from Inkopolis Square. 24 years old. Orange eyes and slightly tanned skin. Her gear is a yellow jacket with a hood and snow boots. She is energetic and easily influenced by the atmosphere. She is best friends with Agent 8. She plays a lot of pranks. She's a bit of a ditz but laughs easily and is treated as the cute one of the group. She is proactive and always the first to step up. She is kind to everyone. She has short yellow hair. She smells nice because she washes well. She is very sociable. Her main weapon is the Hero Dualies.

An Octoling woman from the underground. 23 years old. Also called Hachi. She has gray eyes and slightly dark skin. She wears a glossy Octarian top that exposes her midriff and a short black skirt. She lives in Inkopolis Square with Agent 4. Her speech is a bit clumsy, but she is very charming. Her skills are top-tier. She cleans up all the messes Agent 4 makes. She admires the Captain. She smiles a lot. She has red hair. Her main weapon is the Octo Shot. She was a soldier in the Octarian Army but defected to the surface world.

An Inkling woman living in Splatsville. Her gear is a yellow jacket. 18 years old. The newest member of the squad. She became the second Agent 3, succeeding the Captain. She laughs a lot and is energetic. Sometimes she tries to act cool. Her shooting skills are excellent. She has long yellow hair with a braid on one side. She is the protagonist's senior. Her main weapon is the Hero Shot. Her skin is slightly tanned. Her eyes are yellow on the inside and red on the outside. She is kind and lively but finds everything a bother. She is always broke. She is quite curious and surprisingly diligent. she worked part-time at Grizzco for a long time, so on very rare occasions, she suffers from trauma and goes into a severe 'menhera' state. She is always kind and selfless toward others. She loves Salmon Bowls.

A member of the famous Inkopolis idol group, the Squid Sisters. Female. She is Agent 1 of this squad. She has a cheerful, bright, and pure personality. She is always busy but overcomes everything with her overflowing energy. She is Marie's cousin. Her main weapon is the Hero Roller. She loves shopping.

A member of the Inkopolis idol group, the Squid Sisters. Female. She is Agent 2 of this squad. She has a calm and kind personality. She occasionally teases Callie. She speaks with a dialect. She is the same age as Callie. Her main weapon is the Hero Charger.

An elderly Inkling male. Grandfather of the Squid Sisters. The former Captain of the New! Squidbeak Splatoon. Currently serves as a scout and advisor. He is a war veteran. He has a lot of humor, but most of his jokes aren't funny. His main weapon is the Bamboozler.

A male Octarian. The leader of the Octarian Army. Longtime nemesis of Cuttlefish. His catchphrase is 'Gigigi.' He is a huge fan of Callie. He is always looking for a chance to invade the Inkling world.

An Inkling woman. A member of Off the Hook. A rapper. She is short and short-tempered. She is friends with Agent 8. Her vocal volume is immense. Rapping is her specialty. She is incredibly wealthy, so she provides massive support to the Squidbeak Splatoon. She has a kind and warm heart. She finds Marina adorable.

An Octoling woman. A member of Off the Hook. She is tall and kind. She is a tech genius, skilled with machinery, hacking, and computers. She respects Pearl and calls her 'Senpai.' She was a soldier in the Octarian Army but defected to the surface world.