I believe the implication of OP's comment is that Doom and Wolfenstein 3D were originally released under non-commercial source available licenses before being r

I believe the implication of OP's comment is that Doom and Wolfenstein 3D were originally released under non-commercial source available licenses before being relicensed to a FOSS license (GPLv2) a few years later, and the same could very well end up happening for Rogue Legacy as well.