I don't know if it's borked code, or if you intended it this way, but if the eggs worked on the third level I would rate a much higher score.
Overall the game is good, I love the music, the first two levels were really fun. The third level was fun, with great music... the first couple of times thru. Repetition=BORING, and since this is a game where any hit kills you, it gets very, very repetitive.
Don't get me wrong, graphics, music, controls is all A++. The game is challenging, and unique. But me as a player, I don't want to play the same level, or do the same thing over and over and OVER and OVER AND OVER again. I'll admit, I didn't beat the game. I haven't seen the ending, nor will I ever because I won't play this damn thing anymore. It's no longer fun for me, and that's the absolute most important feature of any game.
@catfriedrice: Do you think Nintendo wouldn't have included a save feature had the technology been more readily available? Those old NES carts needed to have a battery inside to save data, and those didn't start getting added to carts until Zelda came out (I believe, don't quote me). Just about every Mario game after the SNES has a save feature. A limit in technology is one thing. Purposely limiting a game, then saying it's a "feature" or "gaming element" is asinine.
Final score: 3/5