PocketMatrix

I think that the best way to protect it would be somehow like the Snails are, if you have them.
Actually some other programs are protected this way too.
When installing it, it needs to contact the site and check the serial key, some keys can be blacklisted, so it makes sure that leaked keys are no longer usable.
I bought this game because of this , otherwise I would have a warez version.

That's true.
Just telling you what a good protection is.

I'm pretty sure that it's gonna be cracked and released, but make some protection anyways so the crackers will have harder work.