That's what op is saying, the engine is GPLv2, but the assets are copyrighted. There's Freedoom though and it's pretty good [0]. [0]: https://freedoom.github.i

That's what op is saying, the engine is GPLv2, but the assets are copyrighted. There's Freedoom though and it's pretty good [0]. [0]: https://freedoom.github.io/ https://freedoom.github.io/