Submission #4913: xy2_'s NES Dr. Jekyll and Mr. Hyde in 17:27.41

Console Nintendo Entertainment System Emulator Bizhawk 1.11.3
Game Version USA Frame Count 62948
ROM Filename Dr. Jekyll and Mr. Hyde (USA).nes Frame Rate 60.0988138974405
Branch Rerecord Count 9130
Unknown Authors xy2_
Game Dr. Jekyll and Mr. Hyde
Submitted by xy2_ on 11/19/2015 6:09:16 PM

Submission Comments
Dr. Jekyll and Mr. Hyde is a action-packed strategy "dodge 'em up". Agent Jekyll, undercover agent, passing as the innocous Dr. Jekyll, has the mission to secure the church before the famous terrorist gang, the 'Pink Lincolns', take over the place. Armed with nothing, and passing up as just another innocous civilian, Jekyll has to get through a city riddled with crime. Street bombings are commonplace; as are the trained combat dogs and their owners, the agressive combat cats and the precise headhunters.

Game objectives

  • Emulator used: Bizhawk 1.11.3
  • Abuses programming errors
  • Takes damage to save time
  • Heavy luck manipulation
  • Needs to be watched at 300% speed minimum to be bearable


RNG Manipulation

All of the hasards you see aren't fixed encounters (except for the pink bombers, which are fixed but avoidable; I'll get to that down below), they are random. RNG is crucial to manipulate ennemies so you can hold Right more optimally: you basically don't want anything to bother you. There are two ways to manipulate RNG:
- mini stutter stepping: when you hold Right, Jekyll doens't actually move forward; he cycles through a three frame long animation, goes forward on the fourth frame, then starts another 'going' forwards animation. However, if you stop for 1 or 2 frames after executing this animation, you will still advance, but without fully holding Right, and consecutely never stopping. This method, hovewer, cycles the RNG very inconsitently, and only works once, until the RNG has done a full cycle.
- stutter stepping: same thing as above, but stop for 4 frames (= 1 'ingame' frame).
- jumping: jumping is as fast as stutter stepping, but causes less lag when there are entities on screen, for some obscure reason.
I always try to jump as little as possible, and prioritise stutter stepping when it is faster, because it looks smoother.

Kid Bullet Dodging

Occasionally, the kids will fire a bullet. This is simply avoidable by turning left for one frame then right again: this changes your hitbox slightly, just enough to pass over the bullet.

Quick Damage Boosting

When Jekyll takes damage, he is normally sent flying a varying amount of distance back, based on what hit him: bombs can cause him to be flung several meters across, floating the entire way through. This is why I try to make a quick damage boost: as in, instantely falling as soon as I get hit, instead of floating.

Stair Glitch

When Jekyll scrolls the screen enough so that he is barely able to fit between a 'step' and the corner of the screen, lands on that spot facing left, turns right, then jumps, he will clip out the screen and reappear at the very right of the screen. The most obivious advantage is being able to bypass dog-jumping, since you scroll past them, being at the right of the screen. However, this trick is not used in the run anywhere because of its tremendous setup time (300 frames) and its utility is limited where luck manipulation can do better work in a shorter time. Massively abused in the last screen.

Hitbox Clipping

When you get stuck at the very right of the screen via the stair glitch making it so Jekyll has half of his severed body on the very left of the screen and its other half on the right of the screen, simply holding Left will change Jekyll's hitbox location from the very right of the screen to the very left of the screen. Used to skip all bombs in Screen 6. Note that the bombs in Screen 6 still hit Jekyll from the back, but he only takes LIFE damage as a wierd result.

Perfect Clipping

If you do the stair glitch, then jump into another stair, you will end under the ground. Walking for a bit, then jumping again puts you at the very right of the screen in somewhat incosistent conditions, at the very right position for Jekyll to dodge every obstacle in the game.

Backwards Boosting

By turning left at the exact frame you get hit, you get knocked back while facing left. This doens't have any use, but it used when it doens't waste any time for extra style.

Despawning Sprites

By having perfect timing and RNG, you can completely despawn some sprites from appearing. This is used to despawn the kid in Screen 1 and one of of the spiders in Screen 2.

Despawning Pink Bombers

Pink bombers are crucial: they deal massive damage with their bombs, as well as causing dogs and cats to wake up and civilians to panic and deal damage in very frequent waves. Most of these effects can be dodged, but there is one who's crucial to despawn: the pink bomber at the start of Screen 3. Sadly, these are dependant on an internal timer, and I have to wait 6(!) seconds at the end of Screen 2 to despawn that pink bomber.

Bomb Voyage

In Screen 6, if you scroll a singer on screen while a bomb is on screen, the bomb will reset and snap to your position, and the pink bomber will not come back. Very useful trick.


You might notice there are two types of health: LIFE and METER. When METER is empty, you transform into Hyde, which is to be avoided at all costs. The game isn't supposed to be completed like that, obiviously; there are no heals, and you have to complete the entire game with one health bar, which is really tricky.
The health routing is perfect in the run. The previous TAS chose to take no damage on purpose: I take as much as possible on purpose for damage boosting.

Death by Cutscene

Dying at the exact frame you trigger a cutscene (end of a level) while jumping will trigger the cutscene when landing. Useless, but cool. Used at the end of the game.

Other Comments

This run can't be accurately compared with the published run (FCEU..). Lag frames are emulated really badly. Even then, 2143 frames were saved.
I started this run to improve the currently very old published run and ultimately finished it out of hate for the game. TASing this is equivalent to kindly bashing your head over and over against a spiked wall.
Thanks to arandomgameTASer, for finding a trick early on and doing some WIPs of Level 1. None of his input is left in the run.
Suggested screenshot (frame 57612)

Samsara: Claimed for judging.

xy2_: I'll be cancelling this due to major improvements related to the stair glitch, and a new glitch leading off to it (perfect clipping). The run itself is changed as a whole and has a very different watching experience, which leads me to cancelling this movie and submitting a redone version in the near future.

Last Edited by on 1/1/2022 6:13 PM
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