Wow, what a game. Excellent minimalism, use of pixels, controls, level design, gameplay, atmosphere, color scheme, sound, and personal meaning.
While the graphics were very simple, I liked them that way. The blacks and reds are in high contrast to the enemies and character, which increases visibility and looks good, too. The scenery you made using such basic tools is stunning. The entire "Don't Look Back" concept was really interesting. It added an extra challenge, but not so much as to become irritating. The end was very creative and clever, as well.
This flash is an excellent example of deceptive simplicity in flash game design. To make a game with this much depth and feeling while only showing a surface of spartan, old school graphical interface is challenging, and you fucking NAILED IT. I hardly EVER give 10's in reviews- I mean EVER. During my time as a member of this website, which spans just under 6 years, and over a hundred reviews, I've only given out about 20 perfect 10's. The last time I did was January 2008. You managed to break the drought, man. Kudos.
I'm hard pressed to think of any criticisms, since I don't think I really disliked anything about the game. The final boss was pretty tricky unless you knew exactly how to do, and if you can't figure it out, you're screwed. Even if you know what to do, you still may not be able to physically pull it off due to difficulty. Of course, this issue is greatly diminished thanks to the respawning system, which worked very well, I might add. Even still, I can see some people having a really hard time with it, and some people may give up at that point and not get to experience the glory that is the rest of the game. Maybe make the boss a bit easier after 20 or 25 deaths would be a good thing, if you could possibly implement it.
I eagerly anticipate anything you produce in the future, and hopefully it will be another game like this. Congratulate yourself on a job superbly executed.