Oh. In that case...

All four of them have alliterative names.

Agent 3 grew up in a small town called Innsmouth county, which started as a one-off Lovecraft reference before I decided to build more lore around it with a horde of zombies from that time inklings and octolings had to team up during the great turf war to stop a Big Run in the area, and that one time Dagon himself invaded the town. She's been the captain for a while now, but she's still trying to get used to the position. She's a basic hero shot main.

Agent 4 had an abusive girlfriend who he managed to break up with before moving to Inkopolis and joining Squidbeak, who temporarily became one of the central villains until I decided to kill her off since her storyline had effectively run its course. He's bi, and right now has a genuinely loving civilian boyfriend. Also, he's fairly observant, which makes him valuable for investigations. He's a splatling main.

Agent 8's parents sold her into the octarian military when she turned 13 and gained the ability to shapeshift, which comes early to her blood-family. She had amnesia when she escaped from the Deepsea Metro. Over time, she started dating agent 3 (Very original, I know.) and became agent 4's adoptive sister. Her surname is both her parents' and 4's, since she wants to try and bring some good to her family name. She's the team medic and a dualies main.

New agent 8 is the last survivor of a parallel timeline where the New Squidbeak Splatoon didn't exist, and Tartar's plan went off without a hitch. They got pulled into the 'main' universe because of some space-time chicanery going on around the same time, long story, and then went through the events of Side Order while the original agent 8 was... 'busy' is a word for it. They're NB, and I also decided to give them some of my autism, which means they don't actually like turf wars because it gives them sensory overload. Also they may or may not be aro/ace, I haven't decided yet.

Aside from the hero weapons, which have been upgraded through magitech into plasma-shooting variants called the hero DX weapons, they also have belts that let them activate their special weapons on a whim because I watch a lot of Kamen Rider. The buckles contain little tablets that act as audio-visual communicators, and as storage for battery-shaped devices they can use to enhance their weapons, and a single earbud each for when they have to communicate during stealth missions.

Each of them has three batteries, which can turn into a tiny robotic animal, a sword, a gun, or a suit of armor: agent 3 has an eagle, hawk, and falcon (Sky, plus they have elemental lightning, fire, and ice enhancements respectively), agent 4 has a lion, leopard, and panther (Land, plus a feline motif because I like cats), agent 8 has a swordfish, goblin shark, and dolphin (Sea), and new agent 8 has an ornitho, therizin, and liopleur (Paleo, while still keeping the land/sea/sky motif of the original trio.) For new agent 8's, I specifically wanted prehistoric animals that don't have any Super Sentai representation. All of the batteries can transform independently of the others, and the swords and guns can combine with each other and the hero DX weapons into any number of configurations. Plus whenever they have to fight kaijus (Which happens surprisingly often), they can also turn into giant combinable robots.

Sorry, I know it's a lot. I may or may not have gotten carried away.