Tool-assisted game movies
When human skills are just not enough

Submission #2373: adelikat's NES Contra "pacifist" in 09:41.36

Console: Nintendo Entertainment System
Game name: Contra
Game version: JPN
ROM filename: Contra (J).nes
Branch: pacifist
Emulator: (unknown)
Movie length: 09:41.36
FrameCount: 34939
Re-record count: 15434
Author's real name: adelikat
Author's nickname: adelikat
Submitter: adelikat
Submitted at: 2009-08-12 20:20:14
Text last edited at: 2015-03-27 19:04:38
Text last edited by: adelikat
Download: Download (6493 bytes)
Status: published
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Author's comments and explanations:
Disclaimer: No aliens were harmed in the making of this TAS


This is an improvement of 245 frames over my previous Contra pacifist movie.

I recommend downloading the release package from my TAS SVN.

This package includes:

  • The movie file & this submission text
  • Savestates for every area (Windows users can just drag & drop them onto the emulator to view any area in any order)
  • A spreadsheet showing frame comparisons to my previous movie
  • 2 memory watch files that were used in the making of my contra TAS movies.
  • A /Fails folder demonstrating the two ideas I had for improving the area 3 boss/area 4 using the spread gun and how the end up being slower.

I started this improvement in March of 2007, shortly after finishing my 2-player version of the game. While doing the 2-player version I had found one extra place to do the "Jumping glitch" in area 3 (explained in Area by Area). This would save 60 frames in the pacifist version. I redid my published movie (starting from that spot in the movie) and got to the boss 62 frames faster. However, I got an idea that might improve the movie further by trying to use the spread gun on the area 3 boss & area 4. The idea was difficult to test and caused me to lose motivation and ultimately abandon the movie. This summer I created my adelikat-TAS SVN. In the process I began uploading all my old unfinished works. This led me to tinkering with this movie again and regaining my motivation.


  • Idea 1: Get the spread gun in area 3 and use it through area 4
    • Pros: Beats the area 3 boss 290 frames faster
    • Pros: It is indeed possibly to do the "single stream" spread technique in area 4 while still not harming enemies, with only minor losses in frames.
    • Cons: A lot of time is lost on the first screen setting up the spread optimizing (about 50 frames)
    • Cons: Time is lost by having to avoid killing enemies with the constant stream of bullets
    • Cons: The real problem comes from not having an R upgrade (which causes bullets to be faster). An R upgraded regular weapon is superior to a spread gun that is not R upgraded. Therefore in this scenario, the 290 frames saved on the area 3 boss will be lost by the end of area 4.

  • Idea 2: Get the spread gun. Then beat the area 3 boss, but die just as the last shot is delivered to the boss.
  • Pros: It is possible to have enough extra lives and still do this by shooting and getting all the weapon upgrades in area 5
  • Pros: Avoids the losses due to having a spread gun
  • Cons: Again, the lack of the R ugrade. This casues about a 20 frame lost for each turret needed to be shot. This adds up to well over the 290 frames saved by using the spread gun on the area 3 boss.

Misc. notes

Area by Area

  • Area 1 & 2

No change from the published movie

  • Area 3

Total improvement: 91 frames

I used the "jump glitch" one more time to save 60 frames. I used the "anti-jump glich" twice to save 2 additional frames. I fixed a logic flaw in the boss fight resulting in 29 more frames. The error was jumping up and shooting the first 4 bullets at the peak of a jump. The correct logic is to shoot them from the ground and then jump and shoot the 2nd "round" at the peak of a jump. I nor anyone that watched the published movie ever noticed this error.

    • The jump glitch

This is a glitch that takes advantage of the vertical screen scrolling. By moving left then right while jumping up, it is possible to jump a greater distance than usual, resulting in landing on platforms that would normally be impossible. Each time this is done, it saves the time it takes to make 1 jump; which is 60 frames.

    • The anti-jump glitch

The glitch can also be used to shorten the distance you jump slightly. This is done to make sure to land on platforms 1 frame sooner than you would otherwise.

  • Area 4

Total improvement: 25 frames

3 frames were improved in room 2 with a bit of input trickery. 22 frames were saved with an altered strategy on the 3 icons at the beginning of the area 4 boss.

  • Area 5

Total improvement: 58 frames

Nearly all of these frames come from an improved boss fight. I used a strategy of jumping while delivering the shots. This was originally pointed out by Truncated in my previous submission.

  • Area 6

Total improvement: -12 frames

Murphy's Law of TAS: If a game is afflicted with unmanipuatable randomness any improvement to a TAS will result in worse randomness.

The area 6 flames and the area 7 claws both are random and determined by a global timer: 001A. This timer counts 0-255 and runs continuosly while the game is running. Therefore, it is not manipulatable.

In both area 6 and area 7 I got wrose randomness than my previous movie; resulting in lost time.

In area 6 the time lost was greater than any time I gained. So my net time was 12 frames slower than the published movie.

I lost time on 2 of the flames which cost 47 frames. I gained 32 frames on the boss. I gained a few frames here and there in addition to that.

  • Area 7

Total improvement: 76 frames

I lost some frames due to worse claw randomness but also got some better randomness too (I think a net loss overall). I found a number of time savers by using better strategies dealing with the claw sections.

  • Area 8

Total improvement: 7 frames

Improvements here come from 1 less jump, and very marginal improvements to the 2 bosses.


  • Pacifist (no killing or harming enemies unless it is requires to comlete the game)
  • Aims for fastest time
  • Manipulates luck
  • Genre: Shooter
  • Emulator: FCEUX 2.1.1 (Actually it was started originally in FCEU 0.98.16)

mmbossman: Accepting as an improvement to the published movie.

ShinyDoofy: Will process...

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