"So it makes you want to win." YES. Mega Man 9 is another great example of this. Both games get incredibly difficult, but only so difficult that one's inabilit

"So it makes you want to win." YES. Mega Man 9 is another great example of this. Both games get incredibly difficult, but only so difficult that one's inability to complete a level is their own fault, not the result of any "unfairness" on the part of the level designers. It's too hard, then you get better, then you win. That's how you make a great game, and SMB does it to a T.