Thanks, all these are obvious problems with such mechanic.

It's hard to add unique skills with unique effects which can't be derived from basic rules.

The point is to be able to make any ability possible with this rules.

If you see any specific stuff that can't be done by this rules, it would be great if you write the example here.

I've published the google doc with current mechanic description, if anyone interested: https://goo.gl/bsYjX9

There are several "TODO" comments – it would be great if anyone could suggest anything about those things.

In case if anyone interested, I've recently found a pretty obvious thing I have missed before:

to design those custom abilities, I need to design complete magical system/rules first. Not "how to make those abilities" (current thread), rather "how exactly any ability will affect the world".

For now I'm looking and comparing existing RPG magic systems (mostly from tabletop games), but anyway will need to design own system for my abilities. To make it simpler, let's assume that abilities can only affect characters (players, NPCs, mobs) and can't affect world/environment (terrain, buildings, etc).

One possible way is to make each object to have a property for each particles type. E.g., Temperature for Fire, Wetness for Water, and so on.

So, particles will affect own property and it will results in some visible effect.

The hard part is – while things like "temperature", "wetness" or "health" (for Life/Blood particles) are obvious, I'm not clear what to do with Earth (strongness?) or Air (?), not talking about other types...

Trying to think any other ways how to design it on low level, but didn't yet found anything.

Hello! It's quite an interesting thread over here, thanks everybody for posting their thoughts.

My two cents here - just wanted to point out that there is a Magicka 1 and 2 games designed around skills customization. Maybe you've heard about it, but just in case if you haven't I recommend checking it out. It's not quite 'customize everything from scratch' but not exactly predefined as that classical RPG of yours either.

So yay, nice work! Waiting for a playable demo or prototype :)

Hello! It's quite an interesting thread over here, thanks everybody for posting their thoughts.

My two cents here - just wanted to point out that there is a Magicka 1 and 2 games designed around skills customization. Maybe you've heard about it, but just in case if you haven't I recommend checking it out. It's not quite 'customize everything from scratch' but not exactly predefined as that classical RPG of yours either.

So yay, nice work! Waiting for a playable demo or prototype :)

Yeah, I've played Magicka and it seems the closest to my idea, while still not exactly the same... It has some basic rules, but all of the most effective spells are predefined by specific combinations (which is not resulting from the basic rules).

For now I'm still trying to figure it out before making a prototype, because I have lack of details for a low-level mechanic.

E.g., I need some rules of how exactly effects will be applied (damage, healing, slowing/speed up, other things...)