If these cephalopods had never come into contact with the New Squidbeak Splatoon, how different would their lives be?
Terrance
If he had never followed good ol' Cap'n Cuttlefish down the sewer hole...hm...I don't see his life being too drastically altered, aside from the life changing adventure of rescuing the Zapfish never happening.
He'd live the life of any normal citizen of Inkopolis. I think he'd live in the Plaza for as long as he could, at least until practically everyone migrates to the Square, in which case he would also move in search of freshness.
However, he'd never have the experience that made him stronger both as an agent and as a person. And of course he wouldn't be close friends with the Squid Sisters. Still, he'd be a fan of them. He also would never get the battle skills he acquired as Agent 3, but he'd still be a fairly skilled Turf War/Ranked player nevertheless. Just a little less so due to never being an agent.
Juniper
If she had never followed Marie down the manhole...her life definitely wouldn't be as exciting -or as dangerous- as it could have been. Even so, her life wouldn't be too overly altered. Aside from not rescuing the Zapfish...or Callie.
Like Terrance, she'd live like any other Inkling. She'd have plenty to do in the Square, so her life wouldn't be too uneventful. She'd probably find a job to do in addition to playing Turf War.
But she wouldn't have the skills she got during her time as Agent 4. She'd also be more introverted than normal; being an agent of Squidbeak had raised her self-confidence over time. And, of course, she wouldn't have become friends with Marie (and later Callie) due to never being recruited. And considering the fact that she'd never heard of the Squid Sisters even before moving to the Square...
Kazuki
If he had never woken up in the Deepsea Metro...heck, he wouldn't be there in the first place, not if Octo Expansion never happened. Unfortunately, he doesn't have a decent alternative life.
He'd still be a soldier in Octavio's forces, living in Octo Valley with the other Octarians. His daily life would consist of...whatever Octoling soldiers do every day, probably training and patrolling and other military stuff. As to wether he'd be a normal soldier or an elite soldier I couldn't say. Seems more likely he'd be a normal soldier.
Because of all this, he'd never get to see the surface (Inkopolis) unless he was sent on some sort of mission there. And he'd never break free due to never having heard Calamari Inkantation. However, unlike Terrance and Juniper, he'd be a highly skilled combatant due to his training. He'd be very good with technology as well. Sadly, he'd never be able to experience life beyond the Valley. Unless he decided to leave on his own, but given Octavio's controlling music I can't see that happening.
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Squidbeak Splatoon: Agent Random
RandomAbsolute randomness involving my three agents. Various scenarios and very likely to be total cringe but what the heck, here I go. Edit: I'm taking requests now! See the part called "Request Page" for details. Edit (2): The book is full, so I can't t...