The simple platformer that started the series which lead to the famous Duke Nukem 3D and the infamous Duke Nukem Forever! It's an EGA side-scroller with PC speaker graphics and silly enemies.

I used the shareware version (2.0) of episode 1, which is available from 3D Realms. I installed it using DosBox and then created the image from the installed copy, using the directory name DUKE.

Duke is a fixed-height jumper. This makes a lot of jumps look suboptimal, but they're really as fast as is possible. Taking damage resets your jump, a trick I use as often as possible. It's also a bad thing, since you can't just ignore the damage and make a jump, you have to take damage and fall and jump again, or pause to kill the enemy so you don't get canceled. Thankfully you have (partial) mercy invulnerability, so if you take damage at one point you can ignore jump canceling for several seconds.

Duke has three required upgrades:

And three optional ones, all of which are bullet upgrades. The upgrades only let you have more bullets on screen at once, they don't increase damage. I get the first (in stage 4) and skip the second (stage 5) and third (stage 10). The second is too far out of the way and the third is only usable on the final boss. It's very very rare that the second would help (I never have that many bullets on screen anyway) and the third would be completely pointless as I'm feeding bullets to Dr. Proton at point-blank range.

How to start the first level was one of the trickiest parts, since you can only jump 3 spaces on this level and the blocks just aren't laid out in a way to let you do that quickly. The jumping to the key is also tricky, since if you do it naively as fast as possible, you'll miss jumps and have to wait longer. Pausing at several points as I do and taking "worse" jumps actually results in better speed. Finally, I wait until the right moment (0:10) to deactivate the hint system: Dialog boxes cancel all input, so it'd slow me down if I wasn't falling straight down. (If I leave it on, getting keys and opening doors pops up even slower dialogs)

This is very straightforward. Frame precision makes shooting through ice very fast!

Finding a route that doesn't backtrack too much on this level was tricky. I avoid shooting the fan at 1:18 so I can use it to push me off to the right at high speed. Avoiding the damage in the yellow section with the blue key is possible, but wastes a few frames. I turned out not to need the health, so I happily take it.

And then I immediately burn a bunch of health running through screens and screens of enemies. The breakable bridge requires you to step on it twice, with no way to jump cancel or step off it and back on, I have to waste a full jump to land on it. Getting low on health, I delay a frame to get the chicken powerup (+2 health) and to shoot the mech techbot as otherwise I'd take at least 2 damage from it. I meet the first of the Dr. Proton video screens: These annoying backgrounds pause the game to pop up a message and cancel your input and jumps. Thankfully this one hits while I'm on the ground, the others will not be so nicely placed. I only disable three of the fans, using the last one to shove me into the exit door at high speed.

Easily the most boring level: With lots of long, long, long corridors and very little to do, this level consists of a lot of walking. I delay one frame to pick up another chicken. I'm able to avoid the video screen on the left side by jumping over the trigger, but not on the right side.

The jumps at the beginning are a nightmare: They're all the wrong heights to do at full speed, so there's a bunch of frames spent pausing to set up the next jump. On the way up the elevator I shoot the dynamite I'll be passing by on the way back down, this'll let me start shooting through the ice much faster. I'm able to completely avoid activating the videoscreen this time. For the breakable bridge, I jump against the low ceiling and bounce back on it to break it quickly. I shoot two of the rockets on my way heading left, so the first will be out of the way (and I can drop through) on the way back. I skipped shooting the others to avoid lagging.

I don't avoid activating the videoscreen, so I can make a better jump to the right and get more use out of the conveyor belts.

This level is a nightmare maze when playing in real time, with frame advance and a handy map it turns out to be pretty straightforward. For the fan at 5:28, I pause 2 frames before jumping to allow the scroll to catch up with me, as otherwise you can't shoot it (no offscreen shots allowed). It takes too long to break the breakable bridge, so I just jump around it.

This level is amazingly easy if you know the trick: Head right, head left. If you avoid going above the extendable bridge, it's a cakewalk.

I make the most of the start of level invulnerability, and then take damage from the crawler on the left to avoid jump cancels. I take another hit in the flame pit, to get mercy invulnerability so I can safely jump back up. I jump left in the reactor area to bounce off the ceiling, as a straight jump will go too high and I won't be able to hit the reactor for many frames. I make a great use of the jump canceling at the breakable bridge, letting the mech techbot shove me back into the bridge, breaking it very early. Dr. Proton goes down fast, though I have to pause for two frames to let his shot get out of the way so it won't jump cancel me.

Improvement wise, it might be possible to luck-manipulate Dr. Proton into not firing when he does and saving a few frames at the end. If a way can be found to glitch the 4-block jumping and the slow scrolling, it could save a lot of time by not avoiding enemies or going through walls.

cpadolf: A very nice run that brought me many nostalgic memories and a pair of ravaged eardrums. Accepting for publication.