Duke Nukum I 2.0

Duke Nukum I 2.0 is an exciting game in which you help Duke defeat the evil Dr. Proton. Yes, this is what you think it is: the very first installment of Duke Nukem, from Apogee, and initially released in 1991. That's not a typo in the title, either: Duke really was a Nukum before he became a Nukem.

Here's the plot of this side-scrolling gem: the evil Dr. Proton is plotting to take over the world, and Duke's the dude with the plan to halt Proton's evil deeds. Zap bad guys, collect power-ups, and try to stay alive in this hostile environment. And above all else: don't let the doctor get away with his dastardly deed.