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

Console Nintendo Entertainment System Emulator FCEUX 2.1.1
Game Version JPN Frame Count 34939
ROM Filename Contra (J).nes Frame Rate 60.0988138974405
Branch pacifist Rerecord Count 15434
Unknown Authors adelikat
Game Contra
Submitted by adelikat on 8/12/2009 8:20:02 PM

Submission Comments
Disclaimer: No aliens were harmed in the making of this TAS

Introduction

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.

Fails

  • 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.

Summary

  • 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...

Last Edited by adelikat on 1/15/2022 12:38 AM
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