itch.io

I don't think that's likely, sorry. It's not really designed to be a standalone system, everything is pretty integrated with everything else and a lot of stuff is hard coded to values specific to this game. Plus I wouldn't be able to find or create equivalently high quality os/rf character assets, etc - Seliel put a lot of time and effort into making art suitable for this kind of game and there's nothing else out there quite like their Mana Seed assets.