[rhplus]

Images, music, video, and text would all be under copyright, while characters and logos may be registered trademarks.

[skerit]

Oh yes, of course. I was talking about reverse engineering the code only. Requiring the official assets is a no-brainer.

[derac]

Largely it is legal, but it's complicated. https://www.eff.org/issues/coders/reverse-engineering-faq