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

Submission #5242: dunnius's NES Metal Gear in 22:24.59

Console: Nintendo Entertainment System
Game name: Metal Gear
Game version: unknown
ROM filename: Metal Gear (U).nes
Emulator: FCEUX 2.2.2
Movie length: 22:24.59
FrameCount: 80808
Re-record count: 84110
Author's real name: Michael Dunn
Author's nickname: dunnius
Submitter: dunnius
Submitted at: 2016-10-03 08:40:07
Text last edited at: 2016-10-09 11:50:13
Text last edited by: fsvgm777
Download: Download (9234 bytes)
Status: published
Click to view the actual publication
Submission instructions
Discuss this submission (also rating / voting)
List all submissions by this submitter
List pages on this site that refer to this submission
View submission text history
Back to the submission list
Author's comments and explanations:


(Link to video)

If you watched the previous TAS, you only need to watch from the beginning of the final electric floor before Big Boss (frame 77085-end). However, there were a few minor cosmetic changes that did not affect the timing of the run:

  • Electric floor before Coward Duck (69615-69733) -- Damage timing changed to the beginning of the area instead of end. This is technically more correct in case the of the rare bad timing where the old way would require an additional pause.
  • Gas rooms in building 3 (75521-76948) -- Damage timing changed to near the beginning instead of the end in both rooms, and the second room is more entertaining by letting the rank down sound play. The connecting room between the gas rooms was entered one frame sooner because there was not a lag frame to avoid.


This is a 101 frame improvement over my previous TAS ([3116] NES Metal Gear (USA) by dunnius in 22:26.27). The big improvement this time is the Big Boss fight by 88 frames using a new technique called Boss Lock, as well as a different route that was originally discovered by coolkid, and made usable in a TAS by using Boss Lock, which makes Big Boss move left sooner. This also avoids both damage from Big Boss' bullets which means that damage can be taken in the previous rooms, which saved 12 frames including 2 from starting Big Boss' text sooner. Then there was 1 less lag frame in the final elevator because the game wanted to be a honey bun and have 101 frames of fun. (Speaking of fun, this is submitted on my 40th birthday to the minute.)

Boss Lock is the method of using the pause glitch to prevent a boss from taking any actions, so the boss will hold still and look stupid. The timing of the pausing depends on the boss since they have different timing for their actions, and it will not work on bosses that act at an interval less than six frames because it takes 2 frames of input in order for it be accepted, and the press has to be released for a frame to be accepted again. This also does not work on regular enemies or pitfalls for that reason, which was disappointing. So this only works on 5 bosses: Shotgunner, Machine Gun Kid, Twin Shot, Coward Duck, and Big Boss. The TAS only uses Boss Lock on Big Boss because the other bosses can not sped up by using it; it costs 3 frames for each pause. This could have been used on Coward Duck if the timing on his boomerang throw was bad, but the previous TAS (and this) had good luck, so it was not needed.

The concept for the new Big Boss route was discovered by coolkid (and is named the Coolkid Route), but was not originally usable in an any% TAS because it required a menu which took too many frames. But by using a series of pauses (10 of them for a 30 frame cost) at the beginning instead of the menu, it saved enough frames to make it faster than the old route with the Boss Lock used. Then because the new Big Boss route avoided damage, I redid the basement of building 3 with the aid of a bot to determine the route, which saved more frames. Then I realized that there were a few more tricks to reduce the travel time of the rocket (when Big Boss is holding still, Solid Snake can temporarily move into the zone where Big Boss would run away to be closer, as long as Solid Snake is out of there when Big Boss decides to move), as well as adding one more pause to change the timing of Big Boss to be more favorable (and because Big Boss does not move from a pause, Solid Snake can be closer to Big Boss for longer), so I had to redo the fight several times, plus lots of testing at the final rocket to make sure that the timing for reaching the door was optimized. I could have gained 4 more frames if I could do the Big Boss fight faster by 1 frame (I tried a number of different routes) because of the frame rule on doors, which open every 4 frames.


  • andrewg for causing me to think about using pauses on the bosses
  • coolkid for the concept of the new Big Boss route.

Samsara: Happy birthday at the time of submission!

Samsara: Happy acceptance as an improvement to the published run at the time of judgement!

fsvgm777: Oh man, more Metal JEER!

Similar submissions (by title and categories where applicable):