Including DLC, micro transaction purchases, etc. If you got a game for free, please also list your non-infinite next best.
For me it’s Team Fortress 2. $100 total spent on hats and the Orange Box back in the day, 4200 hours plus of fun, meaning 2.3¢ AUD per hour. Initially I thought DotA2 would be my best but it turns out I’ve spent a lot more money in that game than I thought…
My worst is God of War: Ragnarok. Bought it full price for $95 AUD, only played 2 hours and hated it, meaning $47.50 AUD per hour.
Most? Stardew Valley. It’s my wife’s favorite game. The fact that she finds joy in one of my hobbies (that we didn’t have in common before dating) gives me happiness when I’m not playing. I know that’s not quite what you’re asking, but it is how it is.
If I treat all games to yield the same enjoyment per time unit (don’t get me started on that assumption) then it’s just which have I played most. Probably something in the quest for glory series or chrono trigger. I got a chrono trigger save with max stats once. Getting to level 99 was harder than getting enough tabs.
Least? Idk, state of emergency? That was not a great game