Autism is where I think that this get difficult, and where I think a lot of the responses might miss.

Gaming is really seems to be a ‘specisl interest’, especially if it’s one game in particular. And taking that away without any replacement isn’t good, since it’s what your brain needs to self regulate. It’s not so much an addiction as nicotine or alcohol can be, but more like food, or hydration. You need a method of regulation.

If you’re worried about the effects of gaming specifically, then the only thing is to find another special interest that grips you in the way that games/that game does. It sounds like you have an idea already on what that might be. All I can say is that you should try and throw yourself into it head first!