An amazing game, one of Newgrounds best.
This game is the definition of the classic platformer. It is challenging in some points, and easy in others.
the simple graphics are complementary to the design, and the gameplay is well thought out.
I have only two minor griefs about the game.
1. The jump button does not always work at the twitch reflex needed for some of the harder parts. This may be a problem with the limits of Flash.
2. a tad short, there should be a third boss. although, apparently this is based on another story, so I am guessing the two bosses are the only ones mentioned.
Other than that, the game is great. You should really make a sequel, with more focusing on the actual, "don't look back" feature.