Do we even want the setting to be purely fantasy/magical? I think there might be potential for something interesting if we somehow make a hybrid of fantasy and modern (e.g. urban, technological) elements. I sorta got the idea for that just through talking on Discord, but it's not entirely fleshed out.
FF asked about world progression, and I proposed that we could have a "world" themed around each mage and their personality. Something like the happy Water mage living in a tropical paradise, the depressed Electric mage living in a dreary urban (maybe even cyberpunk?) megalopolis, the collected FIre mage having an ornate desert or mountain/volcano palace (maybe with a sort of oriental architectural style, with lots of books and scientific instruments or something), the angry Nature mage having some sort of geologically/meteorologically unstable setting (Forgotten mentioned that Nature is sometimes said to be Earth+Wind, so maybe work that in somehow... stormy sky jungle retreat or something?). And we can probably put together a map at some point.
In terms of gameplay, that might mean going to each world and collecting the mages--with each mage you have in your party, you can switch between them as much as you like, though story might lead to them getting split up on occasion. After thinking about that more, that's essentially how Super Paper Mario's playable characters work, so I don't know how good that would be. But it's an idea, I guess.
I'm not sure what order that would go in, or how it would all end. Maybe a journey to the Dark Witch's castle, some sort of battle, then the Dark Witch escapes and flees to the temple of the Light God, where the mages face her true incarnation? And hell, if we really want to, we could give
those characters unconventional personalities/themes. The Dark Witch is a 20-something art student super obsessed with modern/abstract art and architecture and her entire castle is built in that style, while the Light God turns out to have been into emo/punk/rebellious stuff, has posters everywhere, writes a lot of edgy poetry, etcetera... Okay, we can probably come up with something better than that, but I'm just brainstorming.
Some more potential thoughts on story, loosely based on Peter's idea and my elaborations above: show The story would start out with the happy-go-lucky Water Mage going about her daily business, maybe she has a part-time job as a lifeguard on the beach or something. Suddenly a message in a bottle washes up on the shore: It's an audition poster, calling for the most powerful mages in the land to try out for some theatrical production organized by the Light God with a plot that sort of spoofs the plot of our game. She thinks it's a cool idea, and wants to see if her old friend Electric Mage is interested in joining, since she knows he should get out more to try new things--however, he doesn't respond to her messages, and Water Mage decides to set out on a quest to find him and drag him with her to the audition.
She leaves her beachside village, ventures across the small but wild tropical island she lives on, and sets sail for the main continent--however, halfway through the voyage, disaster strikes and she sinks to the bottom of the ocean. As a Water Mage, she can obviously survive underwater... but only to a limited extent, and she needs to make it to the port of the big city. Adventures on the ocean floor and through deep-sea caves surprisingly lead her to the irascible Nature Mage, hiding deep underground (and causing earthquakes and minor volcanic eruptions in his fits of rage). She asks him if he's heard about the play being put on by the Light God and if he wants to join, but he angrily starts asking her why she's treating such a serious matter like it's a joke. After inquiring further, Water Mage learns that the Light God sent Nature Mage a message, too, but he was told that there was going to be a big wrestling tournament soon, and decided to come here to train. Both confused and curious about what's going on, they band together and decide to find out what's up and continue Water Mage's quest to find Electric Mage.
They fight through overgrown cave systems infested with packs of aggressive animals and fungi, and explore apparently abandoned (but dangerously explosive and otherwise precarious) mining operations, among other things on their way to the surface. Once they break out from underground into a forest just outside the city limits, Water Mage thinks she finally must have cell signal again, but it turns out her phone was fried when her boat sank and she didn't notice until now. She can't contact Electric Mage now, and they have to find him on foot. Venturing into the dreary, cyberpunk-inspired city, Water Mage looks for places to sightsee and shop while Nature Mage looks for fights to pick. They accidentally get tangled in the dealings of some shady smuggling cartel or something [plot to be determined???] and eventually find out that the leader of the ring is Electric Mage's twin sister, who turned to this business to provide for her aging mother who's suffering from a rare disease and for her little brother (Electric Mage) who can't do that for himself yet. When they finally catch up with Electric Mage, a lot has changed since Water Mage last saw him; though he was always pretty quiet and shy, he's been pretty devastated by the appearance of his mom's condition and seems even more depressed than he used to be. He was offered a medical research position at an organization reportedly founded by Light God in an effort to cure the disease. Electric Mage thought he was too young and distressed for something like that, but he says he's hopeful, because he forwarded this to FIre Mage--an older and more experienced scientist he's looked up to for most of his life--and she said she'd look into the offer. While Water and Nature Mages are even more confused about the Light God's antics than they were before, Electric Mage decides that now would be a great time to go visit FIre Mage at her lab and see if she's made any progress, and Water/Nature tag along because they don't know what else to do.
Forest/mountain adventures.
A quiet, old village situated between the sides of a mountain and a dormant volcano. Fire Mage moved here several years back and built a laboratory/observatory in the caldera of the volcano, since it's a nice spot to view the stars and the volcanic soil creates a unique ecosystem. When the other Mages find her, she's surprised and embarrassed, having to awkwardly explain that she didn't actually take up the offer, and she's been instead doing a lot of magical reading and research because the Light God sent her a message warning of dark forces emerging in the realm, and asking for her help to gather knowledge and strength to fight back if necessary. The other mages don't believe it, considering how wildly different all of the messages have been--but suddenly another arrives, calling for immediate help, as a Dark Witch has been gathering an army deep in the rainforest (strangely enough, near where Nature Mage normally resides) and plans to march on his temple and vanquish the powers of Light from the world.
They go deeper into the forest, which turns into a jungle. Stuff happens.
That got a lot longer than I expected it to. I'm not super fond of any of it, because I was mostly just vomiting ideas at my screen, and it could use a lot of fleshing out. But it's an idea I guess.
I'm not entirely sure how much time I'll have to work on this once school starts, but I'd be okay helping with story/character stuff, and if I try to learn Godot or whatever engine we choose, I can potentially help on the programming side. Otherwise I'm at minimum interested in continuing to help with general game design and concepts, though that's kind of everybody's job currently.