Submission #8890: The8bitbeast's SMS G-LOC: Air Battle in 03:31.52

(Link to video)
Sega Master System
(Submitted: G-Loc Air Battle)
Bizhawk 2.9
G-Loc Air Battle (EBK) [!]
Submitted by The8bitbeast on 2/10/2024 1:26:29 PM
Submission Comments
This is a TAS of G-Loc for the Master System completed using the Ace difficulty in 3:31.522 real time and 78 seconds game time. It’s a special project for me since I had made a couple of old TASes, including this game when I first learnt how to TAS back in 2012. While these TASes were unoptimised, they helped me gain a love for the hobby and taught valuable skills I’m still using 12 years later. This is now the last of that original set of TASes I did in 2012 that has been redone properly.
Note: I’ve made a video here talking through what the game is, along with the tech used in both RTA and this TAS:

Point Requirement and Difficulty setting

This TAS uses the Ace difficulty which is the hardest difficulty on the game. One of the main differences is the points required to beat the game. The Ace difficulty requires 210 points to win, although you only actually need 170 points to trigger the final boss. If you somehow beat a level with over 210 points, it will trigger the credits regardless of whether that level was the final boss, although this is impossible since there are no levels that give over 40 points. Now for the real question… should this TAS be categorized as using ACE?

Level Choice

Each time you enter a level, you have the choice of 4 different missions to pick from. Here you can choose between types of targets to take down (planes, bases, tanks, warships or bosses) and you can also choose the terrain (which doesn’t seem to affect much). Each mission awards a different amount of points, generally with more targets to defeat giving more points.
I originally thought that the missions were randomly generated, but on closer inspection you always get the same missions on each round, with the exception of the last which can be a normal mission or bonus mission (bonus missions award extra missiles and time rather than points).
Whether you get a bonus mission seems to be influenced by your amount of missiles remaining and also whether you hit more enemies than the target amount on the previous mission (this can be done by attacking a group of 3 when you’re only 1 away from hitting the target amount.
When played to optimize for points, you can beat this game in 9 rounds. Unfortunately that would mean either completing one of the boss battles, or multiple plane missions. Given these both take over 2x longer than a base, tank or warship mission, it was actually worth completing 10 rounds, to completely avoid fighting any planes or bosses (apart from the last boss). It’s just one of those cases where any% is faster than low%.
I actually took a bonus round in this TAS. I didn’t really need the missiles from it, but I did it because it was faster than doing a normal round. This means I technically only played 9 rounds for points which is the lowest possible amount. But I still couldn’t have done it on the first 9 rounds because the points scale up into the later rounds.
One thing worth noting is that you can trade in your points for missiles, time or damage restoration. I didn’t do this in the TAS since it would be slower to lose those points. Usually this is a bad strategy, apart from just before the final boss since you would have hit your point quota by that point anyway.
The missile point trade in system also has an interesting glitch. If you could finish a level with 0 missiles, you can actually underflow the missile count down to 255 and then trade all of those missiles in for points, essentially letting you get enough points to complete the game right away. This glitch is not possible in practice because you will always be awarded at least 10 missiles for completing the level, meaning you can never come into that screen with 0 points.

In game tech

You can press the 2 button to fire missiles and the 1 button to fire bullets. Generally missiles are preferred since they home in on the target and always destroy the target in one hit. This allows you to hit the target from further away, which then allows the next target to spawn in sooner (since you’re only allowed to have 3 targets spawned in at once). In the plane levels, I was using the bullets, but none of those ended up being needed in the TAS, meaning that all of the normal levels are done entirely with missiles.
Missile amount management is crucial in this game. Each level gives you 10 missiles + one extra missile for any extra enemy you destroy over the target amount (this can only be done by killing a group of multiple enemies at the last moment). With the early levels, the number of enemies to destroy is lower than 10, so you will gain missiles, but the later ones cause you to lose missiles very quickly. One method to preserve missiles is by hitting multiple enemies with the same missile. This can occur if the enemies are grouped together in close proximity and is fairly easy to pull off RTA. In RTA there is the danger of committing to it without being guaranteed that your one missile will take out multiple enemies, but in TAS you can usually hit 2-3 enemies every time with a missile. If it didn’t work to take out multiple, then moving around the plane usually helps to fix it. The issue with using this is in the case where you have two enemies grouped together and a third off on its own. The ideal situation would be to hit the pair with one missile and the third one with a second missile, however a lot of the time the missiles will target in on one of the two paired enemies each and not the third one. This can be fixed by experimenting with different plane rotations to change the missile priority targeting or by pulling the pair off screen by moving the plane between firing the first and second missile.
The bases and tanks mission start off as the most optimal mission, since they seem to group up nicely. These usually take about 20 seconds whereas the planes or bosses take about a minute (which is why we do an extra round just to avoid planes or bosses). However, tanks and bases become worse in the late game due to the addition of helicopters. Destroying a helicopter will not add to your total, but you still need to hit them to get them out of the way so that the next group of 3 enemies can spawn in. The breakdown of helicopters vs tanks or bases seems to be pre-set. Otherwise I could manipulate them away. For this reason, warships become the best mission for the late game.
One small optimization at the end of each level is to pull the plane up into the air and level out the angle. This saves some time, since that way the game doesn’t have to correct the planes position and angle before the end of level screen.

Final Boss

The final boss fight plays differently to the rest of the game. It’s the only thing in the TAS that doesn’t go down in one hit and for that reason, I need to alternate shots with 1 and 2 to deal optimal damage. The 1 button can deal 1 damage every 7 frames and the missiles will deal 1 damage for each missile that hits the plane. If you hit one of the bombs left by the plane, you will lose your shot to it and not deal damage to the plane, unless the bomb that you hit was still close enough. This can be useful in casual play since you’re getting rid of a projectile that could have hit you, but it’s frustrating in a TAS since we’re not short on health and it wastes valuable damaging time.

DrD2k9: Claiming for judging.
DrD2k9: As mentioned in the review. optimization look solid.
I think this can be a baseline run and doesn't (currently) need a branch/goal name; thankfully that will mitigate confusion between an "ace' branch and and "ACE" branch. If we need to add a branch name in the future, "ace difficulty" may be warranted in order to help prevent confusion even thought we don't normally include "difficulty" in branch names usually going with "easy", "hard", etc.

despoa: Processing...
Last Edited by despoa 1 day ago
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