Am I free to create a character sheet on a mashup basis with a charactermancer?

Hey everybody, am I free to create a mashup character sheet and work on a 'compendium' to implement it as a charactermancer? I mean, I don't see much freedom to 'invent' other magic - I can basically say floating and mean levitation, so why not call it levitation in the first hand? Or I create a "Mesmerizing Song" which has the meaning of "Crission's Pixie Strike", so I name it "Song of the mesmerizing Pixie". Or whatever. Ideas, they're floating in my head like a fae through Greater Faydark. Wait! I get back to topic already... It's just gets a bit complicated when it think of dice, as I do like the ruleset of DnD. I would "improve" the skillset, the abilities, the features, the spells and of course the rules based on my own opinion but I think most players would recognise them as DnD rules. But it is the same with names: it's difficult to come up with something new here as well. When I mash them up to a new system which could remind someone of DnD ruleset, is that even a copyright infringement? Or should I take out my supersecret prime number ruleset (PrimEvil) with d3, d5, d7, d11, d13, d17 and d23? (for technical reasons this only works on computers) I am asking myself: How free am I to realise and publish this sort of mashup project here on roll20? And how much of my ideas needs to be "published" to be accepted as a compendium which I would scribe as a charactermancer? I know, complicated stuff and I didn't know if i should have posted it here or elsewhere. Thanks for reading. Bjoern

There's no way yet to add your own compendium, or modify an existing one.

Thanks GiGs. Hm, what a shame. Though I don't want to modify existing compendia (compendiums?) - I want to have one myself. How does that work? Do I pay Roll20 for their work creating a compendium for me? Or do they fund it with buying my ruleset/books in their roll20 shop? Thanks Bjoern

Here's some background info: Creating a Compendium expansion takes several dozens of hours (or more, depending on the size) for s skilled and dedicated programmer who is already experienced in the process. Creating a brand new Compendium for a new system takes a team hundreds of person-hours. It is not undertaken lightly. If you are looking to expand a homebrew game, there really isn't an economically workable solution. If you are a game developer, you can contract with Roll20 or contract with a small team (you'll likely need an artist and maybe a dedicated character sheet coder) to do the work. This would be in the thousands of dollars range. The Compendium is not simple. To answer your legal questions (IANAL): For your home game, you can do whatever you like with the rules. Even if you are going to charge players to play your home game, you can do whatever you like with the rules. That's hard baked into the (5e) ruleset itself. You are the GM, you can interpret and modify as you see fit. If you intend to publish the rule set changes, though, consult a lawyer . Really. Truly. I do freelance work for a tiny (one-person) company that produces monster and magic item cards for the 5e and other systems. You can bet he has and consults a copyright lawyer.