I want to know if it is plausible to allow free hosting by anyone on your game with shared savefiles and not expect people to hack them?
My logic here: I want to have shared savefiles across servers and not have dedicated servers, but it seems that any 'defense' I put in place would be counteracted with relative ease.
So: Is there a way to make this possible? Or are dedicated servers the only even moderately safe way.
The only two ways I can think of sharing savefiles being possible is a central MySQL server and storing the files locally. Are there any other possibilities here?