Submission #1581: adelikat's Genesis Mercs in 09:52.90

Console Sega Genesis Emulator GENS
Game Version any Frame Count 35574
ROM Filename Mercs (W) [!].bin Frame Rate 60
Branch Rerecord Count 11776
Unknown Authors adelikat
Game Mercs
Submitted by adelikat on 5/28/2007 12:19:31 AM

Submission Comments
This is an improvement over gather's published movie by 26.5 seconds (1592 frames).
Like his movie, I play the arcade mode, and play on hard difficulty and use the code to get faster, smarter enemies.
There is also an original mode that has a completely different level layout and it much longer.
Mercs is a contra-like game for the Sega Genesis. So it should be no surprise that I have TASed it ;)


  • Minimizing diagonal movement. The character moves at 1.2 pixels per frame when walking up but only .84 when walking diagonal up. So care needs to be taken to get get the most efficient route planned in advance.
  • Better boss fights - the use of RAM address watching helped tremendously in these cases. It showed that often the use of Merc bombs was slower. Especially once your weapon is upgraded. The ideal situation is to use 1 merc bomb at the end of the fight to finish the boss off. This is because the regular weapon does 4 damage every 2 frames but the merc bomb does an instant 20 plus 3 damage every other frame. So it is slower except at the end when the bosses health is at 20.
  • Reduced lag. Again ram addresses for camera position were helpful here. Also a lot of luck manipulation was done to get the right enemy patterns. Such as manipulating them to not appear near mini-boss sections.
  • Improved vehicle use. Particularly the boat.

Level by Level notes

  • Level 1 - 216 frames
Improvements in lag reduction and hugging corners and soon as possible. Destroying targets as soon as possible allowed me to not have to stop at any point. I also luck manipulated the enemies so that I didn't have to avoid their bullets.
The boss was easy - 3 merc bombs. The fight was improved by about 30 frames were saved from optimal use of them.
  • Level 2 - 145
Route planning was essential here. Also, I reduced lag a lot in the tank section. I destroy the jeep because it is slower to move around the tank and I have to lose it anyway at the next tank. I wedged the jeep between the wall and the tank so the character would not be blown backwards (gather did this as well).
Mercs are slower on the boss so I waste all but 1 before the fight starts. You will see the boss do the "got hit" animation but no hp was lost. Bosses are not vulnerable until there life bar appears. I waste merc bombs as to not get the merc bonus at the end of the level.
  • Level 3 - 181 frames
Much of the improvements come from scrolling the mini-bosses into the screen as soon as possible rather than positioning the character first. Also, with HP monitoring, I was able to maximize the amount of damage done and made sure the character was as high as possible on the screen.
Same strategy on the boss as the previous ones: waste all but one merc bomb, get the boss to 20hp, use merc.
  • Level 4 - 533 frames
The biggest improved level is this one, primarily from the boat scene. I was able to manipulate enemy patterns so the boat appears right in front of the character and other boats do not. Any other boats cause major lag. Also, I optimized the bridge destruction and minimized lag greatly there too.
  • Level 5 - 214 frames
There were a lot of mini-bosses, all of which were done faster. The train was not improved time-wise since it is an auto-scrolling section. But I think I improved it entertainment-wise.
  • Level 6 - 251 frames
By far the most complex level in the game.
  • Note: There were complaints about gather entering the platform on the wrong side (near the beginning of the level). This is the only side it can be entered.
On the laser beams section I used merc bombs in order to pass through them rather than take damage from enemy fire. The invulnerability period for merc bombs is longer so I can pass through two beams from one bomb.
In the next mini-boss section with the flying jeeps and the closed door, I saved 1 frame by getting inside the door before it was destroyed. Not a big savings, but a nice glitch anyway :)
At the end tank before the final boss, I simply walk past it rather than destroy it. Oddly, this causes major graphical glitching. If it is that destructive to the game you would think it would be harder to do :P The graphical glitching has no effect on the run, and goes away at the end of the level.
  • Level 7 - 72 frames
This is an easy level since it is just a boss fight. Most of the improvement in time is just input time savings from using a merc bomb at the end of the fight.


  • Plays on hardest difficulty
  • Aims for fastest time
  • Takes damage to save time
  • Abuses programming errors in the game
  • Manipulates luck
  • Emulator: Gens9z


  • gather - for his previous run
  • aqfaq - for his wip of lv1 and encouragement

Truncated: Accepted as an improvement to the previous version.

Last Edited by adelikat on 1/2/2022 9:40:09 PM
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