So, the setting for SPECTRA (my incarnation of the Universal Table system used similarly in MSH) is a Wahoo-Post Apocalypse setting.

Essentially inspired by Thundarr, Gamma World, Rifts, and the fictions that inspired them (far far too many to list, but thing Kamandi, Magnus Robot Fighter, and Heavy Metal in general) but combined into a more kid-friendly craziness.  

Second Sun's premise is that a starship between Saturn and Jupiter, heavily experimental opened a singularity for their star drive--only it went wild and grew far beyond the drive's design. It merged Saturn and Jupiter and some "extra" mass from somewhere unknown to create a new sun for our solar system. A very tiny violet star.

No that's the "science" side of the premise, but the new sun created a cataclysmic chain of events on Earth, and altered verious stellar alignments, and magic returned to the earth slowly over the centuries. Now there is Super Science (remnants of the world before, some new created by mad geniuses, mutant brilliance and so on.) as well as sorcery.

I was originally creating this for Cartoon Action Hour, and if Cynthia is amenable I may still do so, but I'm trying to avoid stepping on her toes with her own P-A Cartoon setting.

So, the Spectra system comes into play.

So what things does a wild, wooly, post-apocalyptic setting with both science and magic need?

Barbarians! Creature Heroes! Mutants! Magic! What else?

It sounds cool. I'd immediately raid World of Synnibarr for ideas...

The diamond city, carved from a diamond asteroid thrown out of Jupiter's core when it collapsed (2010: A Space Odyssey style).
Unhappy displaced Jovians.
Mutant bikers, mutant animals,
Robots oblivious to the apocalypse.
Carnivorous mutant jungles.
Aliens.
Extra moons relocated from the vicinity of Jupiter/Saturn/whatever.

I was also thinking about the more problematic science there...
Jupiter and Saturn are fairly far apart - potentially even opposite sides of the Sun (with Earth in the middle) depending on how far around in their orbits.
So imagine the starship drive was actually a 'test run' to go from Jupiter to Saturn that made a singularity at the origin and destination points, pulling one planet through to crash into the other (but perhaps leaving behind its moons and such to start wandering around).

Or it could 'fold' space to put both planets next to each other maybe the intervening space (with Earth in it?) was momentarily shoved into another dimension, long enough for its reality to start to warp.

Cowboys of the Wastes
Friendly Gelatinous Blobs
Volcanic Deserts
Cyber-ghouls
Lava Men
Pterodacty-like Giant Birds
Intelligent Advanced Technology Dinosaurs
Feral Unicorns
Tribes of Cannibal Children
Nanotechnology-using Elves
Warpcrystal
Laser Claymores
Mexican Wrestlers
Zombies From The Age Before
Ruined Libraries and Museums
Fast Food Restuarants turned into Temples
Cage Fighting
Conspicuously Buff Snake-Men
Motorcycle Jousts
Sabretooth Tiger Riding Barbarians
Toxic Waste Wizards
Shaman Bears
Bird Men
Giant Everything- Lizards, Spiders, Worms, Insects
Pocket Facist Utopias trying to Recreate 1950s America as known from handfuls of surviving educational films for school children.
The Great Toad. He Knows All, He Sees All.
Penis-Hating Flying Monoliths

Quote from: Bloody Stupid Johnson;696518I was also thinking about the more problematic science there...
Jupiter and Saturn are fairly far apart - potentially even opposite sides of the Sun (with Earth in the middle) depending on how far around in their orbits.
So imagine the starship drive was actually a 'test run' to go from Jupiter to Saturn that made a singularity at the origin and destination points, pulling one planet through to crash into the other (but perhaps leaving behind its moons and such to start wandering around).

Or it could 'fold' space to put both planets next to each other maybe the intervening space (with Earth in it?) was momentarily shoved into another dimension, long enough for its reality to start to warp.

Dude. "Its magic." The basic idea is things changed, science be damned. Its Science Fantasy Post-Apocalypse. Real science and it do not meet.

More seriously, that's pretty much the base idea, and yes I know they're far apart, but the exact nature is not "understood," in fact as far as anyone knows "The stars were right." Only the die hard Science survivors even have a clue. Its just a back story for a "cartoon" series.

Mind you, I'll tweak it with good suggestions.

I know, I know, I just can't help myself...

While I'm here:

Guys with dark glasses carrying strange religious texts
Vending machines selling cocaine-cola
Techno-wizardry
Cthulhu
Enemy Tribes Descended From Rival Sports Teams
Robots sworn to wipe out all mutants
Evil brains in jars

Evil Brains in jars...

Controlling mutant fishman bodies! Beware The Manchovie hahaha!

eek!

Quote from: Bloody Stupid Johnson;696680I know, I know, I just can't help myself...

While I'm here:

Cool stuff, what about player character stuff?

Also, my friend (an Astrophysics professor) gave me a good reason for Jupiter and Saturn (well, Jupiter at least) because Jupiters magnetic field extends into the orbit of Saturn thus protecting the experimental drive when active from solar particles.

Of course why a spaceship would NEED that, is a good question and not useful, per se, but it might have been in the interest of reducing variables, that might change the devices response.

They also do pass each other from time to time though several AU's distance. Which is doable. Because they wanted something close enough for practical intervention but far enough it wouldn't blow up the Earth

I'd have the PCs roll for random mutations. As far as PC choices, I'd keep it loose like FASERIP and just have several general categories-

Pure born
Mutant
Beastman
Alien
Cyborg
Saurian (dinosaur-man)

For PCs, I've heard mostly good things about the most recent version of Gamma World (e.g. Justin Alexander's review here), with its 'combine two concepts' thing. (even if you stole their chargen system you might outdo them if playing the game doesn't suck so much).
I imagine you'd want a fair range of playable characters, which might suggest you either have broad categories that are fairly reskinnable, or a system where you pick powers to LEGO together your character. The Rifts approach where you design very specific classes one-by-one (Cyber-Doc being different to Body Fixer) tends to give lots of classes.

I second Beastmen (/mutant animals) as a good option since they're good for creating quite a range of possible anthropomorphic critters.

Some existing systems take on this:
Mutant Epoch: Mutant (mild, severe, freakish horror), Cyborg, standard Human, Ghost Mutant, Beastial (sic) Humans (aka mutant animals), Clone, Trans-Human, Bioreplica.

Rifts: most NPC things are also PC things, includes any D&D race, assorted specific Palladium thingies (Gromek, Conservators, blind warrior women...), super-powered humans, baby dragons, psi-stalkers, pyrokinetics, crazies, juicers, you name it. Also various powered armour thingies.

Synnibarr: some of the above things + mutants (basically the "superhero" class), native American shamans, Mage Warriors, Mage Tigers (martial artist/wizards who never sleep), gender-bending androids ('Bio Syntha Cyborgs'), carnivorous Tibetan monks with Strength 400+, Aquaman, psionic secret police, crocodile men who believe humans can only find peace in the afterlife if they eat you, vampires, Amazons, psionic elves who secrete an adhesive substance, birdmen, alchemists who worship technology.

I was going to have

Atomic
Cybernetic
Beastman/Woman  
Magic Using
Technology Bearing
Creature (Strange Mutants)
Mutant Animal
Mutant Plant
Mystic Item Wielding



and combine those with

Barbarian
Warrior/Knight
Sorcerer
Driver
Trickster
Healer
Robot Pilot

Along with a few other key words to do a variety of special templates (premade)

For example:

Ookla the Mok, is an Unintelligible Creature Warrior (or Warrior Creature) so too would be Chewbacca if it were Space Science Fantasy.

While the mutants in the one "race" against Thundarr and his friends would have been a variety of Creature/Mutants, Daring Mutant Drivers


Of course Thundarr himself is a Mystic Item Barbarian..(doesn't quite work) Item Bearing Barbarian? Hrms But he's a Couragoeus Mystic Item Wielding Barbarian



And yes, I realize this allows you to create Atomic Sorcerers, and Plant Knights, and Cybernetic Healers


What others? Prince/Princess? Exile?

Magic Using/ Sorcerer... ?
Tech items and mystic items - may not be much different. I think it may be useful to give (limited) items to some characters outside the class (Sorcerer with magic staff). Perhaps add an 'Examiner'/operator/tech guy class.

Plant Knights seem fine as long as there aren't perverse incentives that make everyone choose the same especially weird combinations.

Depending on how your classes work, Princess or Exile could be a class, just a roll off a social-status table along with Escaped Slave and stuff, an Advantage/Disadvantage, or just chooseable background colour.

Oh and maybe a "survivor from before" class could be interesting (from cryogenic stasis or whatnot).

Well, they're not so much classes as templates. You fit X and Y together to get stats and gear and skills. Plus of course you can just roll up random stats, powers and skills and see what you get..:d