Which game can't you find any flaw with or think of anything you could make better?
Personally I have to say:
- Limbo - I disdained it when I heard how brief it was, but after I played it I think it has just about the right length.
- Binding of Isaac - I'm completely satisfied with what the game provides.
- Fable 3 - I loved the game, its simplicity, variety, its plot, everything.
- Final Fantasy XII - I loved everything of the game, from the gameplay, to the story, everything is so fantastic in my books.