Regro (if uninjured) would fly home and come up with an explanation for the boat rental guy on where his boat is.
This depends heavily on whether the two MCs were marooned with each other or not.
Adi, if alone, would survive just fine. She grew up in a subsistence/bartering society in the deep woods, so other than having to re-figure out what was okay to eat on the island, she'd set up a shelter, start a fire, and hunt/gather/fish for food. She'd be stuck there until another ship picked her up, but she'd be unlikely to die unless the island doesn't have enough resources to sustain a person.
Koreal, if alone, would grumble for a few seconds, cast a teleport spell, and be back in civilization moments later, because he's a wizard. Even if he couldn't do a teleport for whatever reason, he has plenty of ways to escape an island-- flight, breathing underwater, walking on water, cobbling together a raft and conjuring wind to carry him away... He wouldn't stay stuck, is what I'm saying.
If Adi and Koreal were stuck TOGETHER on an island, they'd probably view it as the opportunity to set up a private getaway. She'd get him to help her build a shelter (and probably a nicer one than she could manage alone, because magic), and they'd probably enjoy a tropical vacation alone with each other for a few days/weeks until Koreal got bored, and then they'd teleport (or whatever) back to civilization, leaving behind a way to return to the island if they wanted later. The shelter/resources they left behind may or may not be booby-trapped, however, just in case anyone ELSE stumbled on their private getaway.
Your comic looks like a lot of fun, I'll definitely check it out. Feel free to have a look at my novel and subscribe if you're interested:
Just because it sounds more fun, let's say they were stuck on the island together. I like the idea of turning the place into their own private resort, I certainly would.
I think I subbed to you before, but I'm not sure. In any case, I've subbed now, I really like your art style 
. Feel free to check out my novel and subscribe if you're interested:
Jake: full on panics for a good while. Keeps reminding himself they’re lucky to be alive. Panics a little more, but a bit more quietly the second time around.
Damien: tries to keep Jake from panicking. Let’s him pace around the “base” they’ve “claimed” (aka a tree that gives decent shade) or gives hugs at random. Stresses about getting back to his sisters, but keeps it inside because sometimes feelings are hard.
A few hours later...
Jake: * handing over some branches * “Yeah, we live here now. This is nice. It’s pretty quiet. There’s no one to bother us. I think this might actually be the first time I’ve relaxed in a couple of years.
Damien: * pausing in the middle of the raft he’s building * “Umm, so, should I keep building this...? Or no...?” 
P.S. They compromise and stay for a few months before trying (and succeeding) to get back home.
Well hopefully there is good edible plants, since Zessen is a vegetarian 
she'll probably first try to get some rescue by using her light powers to constantly flash light into the sky to get people's attention. While waiting, she'd probably just live off the land and maybe have an existential crisis or two. But maybe she'll enjoy the quiet a bit since there's no one forcing her to do anything.
Before I answer just wanna say this seems like a good character prompt in case of writers/artists block. Great idea!
Jules: [my city now meme until she’s bored and nopes outta there]
Katherine: I want to speak to the Island Manager
Bob: It just becomes Island Woodstock, somehow
Brenda: “it just becomes Island Woodstock,” Prt 2, Electric Boogaloo
Keith: He starts crying to a volleyball in forty five minutes
Pat: Proceeds to open a tiki bar.
Give up, no question asked. Man is truly domesticated, could never live by himself without somebody helping him
Seems like they have fairly sensible reactions all in all. Pretty normal actually, nice. Good choice on staying for a while, might as well make a vacation out of it right?
your art is really nice. Feel free to check out my novel and subscribe if you're interested:
Thanks, if you're interested, I've done a couple of others. One about characters being trapped in a haunted house, one about where and what people's characters do and go on vacation, and a third about what would happen if people's characters were reverse isekai'd to this world. Feel free to check them out if you'd like.
Haunted House:
Vacation:
Reverse isekai:
Anyway, I see that Cast Away reference there with Keith and the volleyball 
. What does he name it? Katherine sounds like a true Karen, I would hate to be stuck there with her. Everyone else seems like they'd have a great time.
Your story sounds really cool, kind of an Old West vibe to it. I like it . Feel free to check out my novel and subscribe if you're interested:
Ellis would panic, thinking how long it would take for him or anyone else to go crazy and commit cannibalism. Perhaps wondering if they would be killed by natives.
Ross and Meyer are just chilling. They have seen worst. They might be gathering food, creating shelters, and making sure no one gets lost.
Mariel is gathering supplies and working hard to make everything better.
How do they escape? Teleportation, but it takes a while. One at a time. The only person who can do it is Ross, and he takes his sweet time.
Do they want to escape? Ross and Meyer don't have a choice. Ellis and Mariel do want to escape.
Did I do it right? I really enjoy writing this.
The main character of my story is a vegan, chain smoking wolf who is in love with a human.
He would completely lose it and freak out
Lucifer would fly, he has wings for something hahaha If he couldn't, another option would be calling Leviathan and scape easily, as Leviatan can transform into any sea animal and, in fact, they is the sea. If he couldn't do that either, he would find his way to survive and become the king of the island hahaha he's intelligent
Lucifer
Leviathan
For Amèlia, I'm sure she would find a way to survive too; it wouldn't be so easy for her since she's human. She would look for some fruits or food in general to survive. She would make her own place all by herself, maybe even construct a house with the wood of the island's trees and cultivate her own food, as she did in her village when she was young. She would slowly adapt to the island until some ship comes and she can scape.
Amèlia
Yes, my characters are more intelligent than me. I would probably die in two days hahahahaha
https://iridescent.lgbt/comic/blackwings-1/
Yes, you did it right. I'm glad you enjoyed this, I have some others if you're interested:
As for your characters, Ellis seems a little morbid and I wonder if he's okay. Is he always so scared? Ross and Meyer seem to be having a great time, maybe they'll come back. Mariel seems the practical type. Teleportation is a pretty neat way of getting out, though I don't blame Ross for taking so long .
