Prompt Time

We've all had games that we prefer over others, so what is it that you find exhilarating or captivating about your favorite games? If you had to make a game or shape its development, what would you want thrown in, even if the game wouldn't sell or be enjoyed by others? Whether it's the plot, the gameplay, the music, the setting, the atmosphere, the interactivity, or whatever else you might think of, even if it's already been done, share your thoughts!

(This is different from Oliver's earlier post in that it isn't asking about your memorable gaming experiences, but is essentially what game aspects/mechanics you most want to see in a video game, even if it's a really specific, insignificant event in the plot of a side quest.)