I am mildly disapointed in the "boss battles." They are all cake walks. The levels themselves are pretty fun though. Nothing I would consider hard, but a couple spots I died for being too reckless which is a refreshing change of pace from the last few Mario games. Still haven't played worlds 6-8 enough to make a final call on that one. The game is clearly a tribute to every 2D Mario that came before it, and I love it to death for that. Penguin Mario for the win!