It's a campaign setting where characters undergo some sort of transformation when they level up

that's about improving you cahracter by replacing your limbs, not shedding your weaker levels as skin.

Also, what happens if someone gets a hold of your old level sheddings? Is there an economy built around buying and selling sheddings for some purpose? Do people level grind to have enough lvlsheds to pay the bills?

What about elves that change their subrace by peeling off their skin?

>Men turn into cute women

>Women turn into cute women

Inb4 pokemon

They take the sheddings and mix them with some rare ingredients ingesting a higer lvl shedding grants automatic xp at a percentage bjt increases the higher lvl the sheddings are ( so if you are a lvl 5 and ingest a lvl 6 shedding you gain say...10 xp while a lvl 15 may be 150 xp
But if your lvl 14 drinking the lvl 15 shedding you gain 30 ) if you can understand my crazy ramblings

It would also be a valuable market what farmer wouldent pay to get a little experience to take care of his wolf problem instead of hiring adventurers

This would account for why there are so many sub-races of elf.

If they spend too long in a particular environment they start to adapt to it slightly. The old adaptations just sort of peel off.

Forest elf travels to the desert. If they survive long enough their pale skin peels off to reveal dark skin. They also develop the ability to close their ear and nose holes in sand storms and their feet get slightly wider.

Desert dark elf goes to beach for too long and they develop an extra eyelid and their feet start to grow webbing between the toes.

Under an evolution system with minor mutations I would suggest dropping outright leveling for something more like buy what you want abilities like the FFG RPGs where you can just get talents or increase your abilities or whatever using XP. Once something is dead you get XP and can quickly decide what if anything to buy while you are waiting for your turn.

jesus christ SAUCE PLEASE

The Star Munchkin RPG did this for the Bug race. Every time you level up, you die and one of your egg sacs burst open, releasing the new you.

There was this RPG that I can't remember the name but it was like a gameshow but also like a sentai show, except as your defeated monsters you could take their body parts/powers and either temporarily use them like a one off, or fuse it to your flesh permanently to use.

Hmmm...
Where have I seen this before?

Fucking system thinks the link is spam, but the name is Kuroi Majutsu no Susume
WARNING: Contains Futanari

There's a actually a super hero with that power, Husk.

They become more attuned to the astral plane, allowing for magic and magical abilities. This also causss physical changes in a plethora of ways, most often spontaneous.
>Size increase
>Muscle growth
>Increase in physical transparency
>New magical powers
>Increased natural healing
>Immunity to elements.

IIRC, sounds similar to EX gems in Tales of Symphonia. Although, there, soylent green is people.

Its like worm but the agents are even more malicious

Oh, sorry for unoriginal.

What is that.

...

I'd make it a campaign about transhumanism and rather than arbitrarily leveling up, the PCs are instead able to save up enough money to buy the next upgrade/augmentation to their flimsy human body which comes in the form of powers and stat raises and such. Skills are handled by learning them in your downtime.

...

>characters are arthropods/reptiles/birds and must molt

>They also develop the ability to close their ear and nose holes in sand storms and their feet get slightly wider.

Don't forget their knees work both ways now!

You could probably do something with the old adage, "He who fights monsters should see to it that he himself does not become a monster".

Have humans/player races be weak in the setting. Or at least, outclassed. We're talking NPC levels versus dragons, it's just not funny. Humans physically can't stack up, unless they take on aspects of the monsters that lurk beyond the light themselves.
Players level up by taking on more and more monstrous traits. Maybe they have to eat monsters, or sacrifice humanity to patron monstrous beings if you want a touch of dark souls.
Just be careful you don't become the very beasts that you fight, little heroes.

Vaguely reminded of the Magatama from Lucifer's Call/Nocturne.

Now I think about it, it's sort of weird the demonic bug that crawled into your skull via the eye socket doesn't really do much bad to you.

>How do I approach this infinitely expansive concept

Read any beginner's book for aspiring writers and it'll tell you that trying to be creative without imposing any limitations on yourself will lead to you having no idea where to start, and once you do start you'll be sluggish in expanding your foundation.

Are you trying to create a game in the sci-fi, horror, fantasy, or adventure genre? What is the setting? What is the tone of that setting? What are you trying to accomplish by having the characters transform as they level?

You're giving us fuckall to work with.

Not OP, but let's say... fantasy with horror overtones game, in a not!England setting focussing on a victorian-gothic city.
With the aim to invoke a little body horror alongside the loss of one's humanity as the party changes further from their original self as they level.

Of course there's a slight slight problem with some players going "hell yeah, trading in my last vestiges of mortality for a bonus to AC makes me frigging untouchable!", but assue you get a group on board with the setting.

In a previous game (Pathfinder), the GM had it that the fey world was intersecting a real world, and we were slowly evolving/returning to some great creature. Functionally; we each built a super-race with the race-builder, then at each level we'd get one of that race's abilities.

It was very messy.

How about this?

As your character levels up, he/she selects a "path" they want to go on by picking what abilities or spells they want to pursue. When the PC reaches a milestone, they begin shedding their skin and emerge as a more powerful form, more suited towards what they're working for. For instance if they want to pursue nature magic they increasingly become dryad-like A savage warrior might become an orc-like creature for example. Eventually the PC has fully become one of these creatures and has no resemblance to a human.

Thoughts? Suggestions?

The 3e Savage Species book has rules for growing from a basic creature into a more powerful creature as you level up.

There's also a prestige class that is based around the gloriously specific concept of a Rogue using Use Magic Device to equip an item that is normally only used by Drow on their giant spiders.

These options were terrible, but this was 3e, and so was everything that isn't "LA zero species turns into LA zero species with every level in full caster".

>WARNING

Sometimes it feels like you don't even know me, user.

>fantasy with horror overtones game, in a not!England setting focussing on a victorian-gothic city.
With the aim to invoke a little body horror alongside the loss of one's humanity as the party changes further from their original self as they level.
Just do what Bloodborne did, then. It has stuff like the Kosiflower that fits this thread perfectly.

Isn't that how shadowrun works?

Not really, at least as far as I've read.

Why flesh it out? PCs already receive mutations every adventuring week in the form of unnaturally rapid class progression and the physical changes you can just fluff in or have the players play classes like Bloodrager from Pathfinder which involve gaining power from manifesting something (in the instance of Bloodrager mastering the abnormal part of their bloodline and manifesting it more profoundly).

Yes, pretty much.

Depends how your GM wants to do advancement, but there are learning mechanics for skills.