if you could only play one game for the rest of your life, which would it be

It currently has to exist/be released?

Going off of that assumption, probably Skyrim. I'd have to save up for a decent PC and learn the basics of modding but it would be worth it. I already know of a couple of YouTubers who have been playing it and having fun almost constantly since release just by roleplaying and changing up the mods. Still though, I don't think I'd accept those terms for anything less than like $100,000,000. I love video games way too much.