Find me a game

>>55307042
Ars Magica or something

>>55307042
dungeons and dragons

I would suggest Hero System. It's pretty heavy, but once you know it it's a one man band. Most of it's books are simply application of what can be found in the core rule books, which is all you need to put together literally anything you can think of. Learn the core books (and maybe the advanced player guides + ultimate vehicle and base) and you've got everything. With Gurps, the idea is that you get the appropriate book for whatever you're playing, and there's a book for everything.

Another heavy system is Anima: Beyond Fantasy.

>>55307857
> Game mechanics for...

>>55307942
Which edition of hero do you suggest?
I already played anima, i don't think this is what OP are looking for.

F A T A L

>>55308070
Reading 6e isn't as fun as reading 4e, but it's exactly what what the latest edition of a game should be: The truly comprehensive, complete, most modern version of the game. If start with the two core volumes, expanding to the two Advanced Players' Guides, and then to Ultimate Vehicles/Base. Those are all the really generic materials, and with those you'll be completely equipped to run whatever you want if you enjoy the work of building things out of the rules.

After that, you've got big books full of prebuilt stuff. You could build any spell from the Grimoire, any equipment from Equipment, or any beast from the Beastiary straight from the books, these are just resources you can easily just take from.

The genre books from any edition are great reads, no matter what game you're playing. They're full of interesting articles on all sorts of tropes of the genre, plus templates and tips for building templates for things like character archetypes, monsters, and professions.