#8026: Darkman425's GBA Mega Man Zero 3 "Z-Buster only, maximum score" in 1:03:56.27

Important note

While this TAS was created on development build BizHawk 2.9 release candidate 2, it does sync with the released build BizHawk 2.8.

Introduction

Mega Man Zero 3 was an action platformer game released in 2004 developed by Inti Creates and Capcom. It's the third game in the series following Zero, this time investigating the threat of Dr. Weil's return and the mysterious Omega.

MMZ3 is my favorite in the Zero series, even if it's also probably the easiest in my opinion. Each weapon feels fun to use and the revamped elf system actually encourages experimenting with them without penalty. The goal of this TAS is to complete all 16 stages of the game under 3 conditions:

Zero is only allowed to use the Z-buster at all times, excluding the one cutscene that forces the Z-saber to be used.
Every mission score must be at the maximum 100. This means completing any mission objectives correctly when needed and meeting the enemy kill quota of each stage.
A lesser condition that I added to make this seems more impressive to me is to take no damage. While there is a small amount of damage that is allowed before losing mission points due to damage taken, I decided that if I'm going for full score I might as well also make it through without taking actual damage. This does result in some waiting in spots.

Run notes

Emulator used: BizHawk 2.9
Aims for real time
Aims for maximum mission score
Uses only the Z-buster
Very heavy luck manipulation
Foregoes time saving damage

Mechanics and techniques

I would recommend reading the previous submission texts for the other publications for a large amount of the mechanics since they cover them well enough. What I'll add are mechanics that either need some deeper explanation for this run.

#4539: hellagels's GBA Mega Man Zero 3 in 56:31.70

#6660: Geinuhayst's GBA Mega Man Zero 3 "100%" in 1:02:47.71

Elemental weaknesses and boss invincibility frames

Normally when a boss or mid-boss is hit, they gain 90 frames of invincibility that either runs out over time or is restarted when hit by an attack with an increased combo level. When a boss is hit with a thunder or ice weakness that is instead changed to 120 frames, likely a side effect due to how hitting but not killing regular enemies with those two elements also temporarily stuns them. This does not happen when a fire weakness is used.

Z-buster base mechanics

An uncharged buster attack does a small amount of damage. A ground dash uncharged shot is very slightly stronger than a normal uncharged shot and comes out slightly further ahead on screen.

A mid-charged buster shot normally takes 40 frames of holding the buster weapon button (here as the B button but can be swapped around between the main and sub weapon buttons) and does 3 times the damage of an uncharged shot. For repeated mid-charged shots it would be 42 frames between each shot (1 frame for releasing a button between a shot, 1 frame for repressing the button for another mid-charge shot, 40 frames of holding the button to get the right amount of charge).

A full charge buster shot normally takes 120 frames of holding the buster weapon button and does 6 times the damage of an uncharged shot. This is about 3 times the charge time compared to a mid-charged shot. For repeated full charge shots it would be 122 frames between each shot (1 frame for releasing a button between a shot, 1 frame for repressing the button for another mid-charge shot, 120 frames of holding the button to get the right amount of charge).

The cybler elf Clokkle and the Quick Charge head chip can reduce the charge hold time down to 75% of the normal charge time (30 frames for mid-charged shots and 90 frames for full charge shot). The two effects only stack to 50% or normal charge time with a certain equipment combination. However, this combination is non-elemental and doesn't help out with boss fights. Therefore the Quick Charge head chip is skipped in this TAS.

Z-buster specific EX skills in detail

When defeating certain bosses with an A rank or higher going into a mission on Normal and Ultimate mode, Zero can earn an E skill. There are 4 EX skills for the buster, all are full charge shot replacements unless otherwise stated.

Reflect Laser: This skill is earned by defeating Copy X Mk II with an A rank or higher. This requires not having an elemental body chip equipped. When fired a beam will be shot that bounces off a few walls and pierces through enemies it kills. This does a little less damage than a normal full buster charge shot. I do not use this EX skill in favor of having elemental shots ready for bosses.

Burst Shot: This skill is earned by defeating Blazin Flizard with an A rank or higher. This requires having the flame elemental body chip equipped. When fired an initial fireball shoots forward and explodes either after a certain distance or it hits an obstacle that it can't destroy. The initial ball does a small bit of damage and the resulting explosion is 5 small extra hits of damage. Some targets can "fall out" of the blast so that only some of the hits can land, making the position of releasing the shot important.

When unboosted and used on fire-weak bosses, Burst Shot does the same amount of damage as a regular full charge fire buster shot but incurs more boss i-frames due to the explosion hits and thus is slightly slower. Once boosted by another source, weakness damage goes from 9 to a whopping 15 which makes Burst Shot faster on weakness bosses.

Burst Shot also does 8 damage on non-elemental bosses and mid-bosses per shot, assuming all hits connect. This makes it stronger than a normal full charge shot on non-elemental bosses and speed them up by 100 frames, assuming no lag.

The biggest problem with Burst Shot is that it causes a lot of extra lag in cases when there's a few other objects on screen so it's used sparingly. It's also toggled on and off for certain missions until the Busras cyber elf is equipped since using Burst Shot would be slower due to more boss i-frames otherwise.

V-Shot: This skill is earned by defeating Volteel Biblio with an A rank or higher. This requires having the thunder body chip equipped. This causes the Z-buster to shoot double the amount of shots per press, both forward with a slightly vertical offset. This can allow for double mid-charged shots and double full charge thunder shots to be fired. The main problem is that these shots do not have different combo levels and thus can't add damage to bosses and mid-bosses. This EX skill goes unused due to not having enough of an effect to justify taking the time to equip it.

Blizzard Arrow: This skill is earned by defeating Blizzack Staggroff R. This requires having the ice elemental body chip equipped. When fired an ice ball appears an front of where Zero released the shot. After a certain amount of time three icicles shoot briefly move vertically into their positions and them move forwards, in the order of center-top-bottom. The initial ice ball also does damage so for bosses this is fired as close as possible to maximize damage.

On ice weakness bosses this does a whopping 16 damage unboosted and 17 boosted. For non-elemental bosses and mid-bosses this does 11 total damage, assuming all hits connect. This is in theory the highest DPS on non-elemental bosses. Thus once this is obtained the Blizzard Arrow replaces the Burst Shot for handling non-elemental bosses.

There's one big problem with the Blizzard Arrow. Actually getting each part to hit some bosses is an incredibly difficult task. Part of it is that the initial ice ball is incredibly short range and requires getting close to the target, making sure they don't move out of the way. Another factor is that the icicle shots are horizontally offset from the ice ball , slightly more forward from where the ice ball was released. Fired in the wrong place and while the ice ball would connect the icicles will sail right past the intended target's hitbox. Adding to that is that the icicles come out in a timed delay so bosses and mid-bosses have to be manipulated into favorable patterns or else shots will whiff completely. The last part is that due to the vertical offset of the icicles getting the right position to get them to land is much harder on smaller targets.

Damage and combo level for buster shots, and the damage formula

Thanks to this guide by mech_gouki on how the damage formula and combo levels work. The information here is slightly modified from my observations.

https://gamefaqs.gamespot.com/gba/920055-mega-man-zero-3/faqs/30199

An attack combo level system is applied when attacking bosses and mid-bosses. Attacks can be chained into another to inflict damage via a combo level system. Each damaging ability Zero can use has a combo level. If a boss or mid-boss is hit with an attack, an invincibility period begins and Zero can do another attack for more damage if and only if the next attack has a higher combo level.

These extra hits also reset the invincibility period. This prevents doing something like the saber dash cancels found in the PlayStation Mega Man X games but the game is designed carefully where even with those restrictions Zero can do lots of damage quickly.

Damage on all enemies are determined by this formula:

Damage = (A + B) * E * D
if damage > 0 and damage < 1, damage = 1
else damage is rounded down to the nearest integer

Where:

A: damage source's base value
B: damage boosts from sources such as cyber elves and e-Reader card effects
E: elemental effect on enemy, where:
- Non-elemental: E = 1
- Weakness element: E = 1.5
- Same element: E = 0.5
- Immune element: E = 0
D: defense check
- If enemy is a boss or a mid-boss: D = 0.5
- Otherwise: D = 1

Effectively this means outside of elemental weaknesses a +1 to a weapon wouldn't do any extra damage on bosses outside of ground dash uncharged buster shots due to the defense check. For a TAS without weapon restrictions that makes the weapon boosting cyber elves useless, but for a buster only run this makes for faster fights with two of the elemental EX buster skills.

Here's a table of combo levels for each of the relevant skills with the buster.

Damage source	Combo level	Damage	Element
Uncharged buster shot, no ground dash	0	2	None
Uncharged buster shot, ground dash	0	3	None
Mid-charged buster shot	1	6	None
Full charge buster shot	1	12	Any
Reflect Laser	1	10	None
Burst Shot initial fireball	1	6	Fire
Burst Shot explosion effects (max 5 hits)	2 3 4 5 6	2 each	Fire
Blizzard Arrow initial ice ball	1	10	Ice
Blizzard Arrow icicle shots (max 3 hits)	2 (middle) 3 (top) 4 (bottom)	4 each	Ice

Giant Elevator mid-boss note: The mid-boss of the Giant Elevator, Spearook, takes double damage if the top half is knocked backwards. While this may make one to believe that this would disable the defense check, this is not true. What happens is that the resulting damage after the damage formula's applied is then doubled, leading to damage boosts being lost due to the rounding down of damage.

Cyber elf choices

The cyber elves that I decided to route into this TAS are Clokkle and Busras.

Clokkle, as mentioned before, speeds up weapon charge time. This is useful for speeding up all bosses across the board, whether it be a frame per shot for thunder weakness bosses to 30 frames per shot on some fire weakness bosses and the Crea & Prea fights. This also helps speed up killing enemies, either to get them out of the way faster, or to reach quotas as faster mid-charged shots. While it's out of the way the time save is felt across the entire run.

Busras adds 1 damage to the base buster damage numbers across the board, which helps with taking out enemies slightly faster in some spots as well as greatly increasing Burst Shot and slightly increasing Blizzard Arrow weakness damage. Getting and equipping Busras is a small time loss but the reduced amount of Burst Shots needed on bosses alone is enough to justify grabbing it.

200 E-crystal had to be manipulated to get Clokkle ready before the mid-boss of the Ocean Highway Ruins. 100 additional E-crystals were needed for Busras but due to how late they show up in the run no drop manipulation was needed.

RNG manipulation

RNG is called whenever something requires it, such as enemy actions or screen effects. This limits the ways Zero can actually manipulate the RNG but still in a way that reduces time lost due to it:

Firing a buster shot that hits a wall or bounces off a shield since that creates some screen effects that use RNG
Jumping off the wall since a small effect is cause from doing it
Sliding down walls to create dust that affects RNG

There are a lot of cases where I fire the Z-buster at walls to manipulate enemy drops for E-crystals or to manipulate starting boss RNG patterns.

Bosses and mid-bosses use the game RNG and position of Zero to determine their next action, assuming their next action isn't a fixed one due to something like HP thresholds. Thus there are some times where I move away from the bosses to get a better attack to work with.

Due to how RNG works it makes fixing mistakes a bit harder to actually fix since either a lot of work is needed to get the RNG resynced back or work has to be redone with different RNG.

17 February 2023 EDIT: hellagels has informed me of an important part of RNG. It's set to a specific value when entering a stage. That means fixing RNG in one stage shouldn't impact the other ones.

Sunken Library door manipulation

I was really disappointed in how this isn't quite explained well enough to my tastes. So here goes.

At the end of the stage, Zero must find 4 secret disks by entering 4 doors that contain them. There are 8 possible locations they can be in, as shown below:

|A|B|C|D|
|E|F|G|H|

Ideally the 4 doors should all share the same row, which is a 1/70 chance for a given row and 1/35 chance for either row. This is determined by the local mission timer that's running and normally used for the mission score at the end. The door positions are locked in when Zero touches the door to the computer room where the player is intended to check the disk locations. This unfortunately leads to forced waiting for the right RNG seed as this is disconnected from the other RNG seed that Zero can manipulate from actions.

All this is also assuming I don't care about which room is last for the purposes of the boss fight which would lead to even lower odds. 1/280 would be the target normally since ideally it would be the top row for a slight horizontal boost since certain Z-saber involved damage combos are normally used for quick kills.

Since I'm using the Z-buster only that's less of a concern so I just settled with the first shared row. While I could have worked to get a slightly better seed for all top row instead, the potential time saved would probably be negated due to the waiting and the fact that it took almost 3 seconds of waiting for the right seed. There wasn't a convenient script that I could use to quickly check them so those almost 180 seeds were manually checked, which took quite a bit of time.

Argh.

Falling ceiling wall jumping

This was discovered by McBobX but nobody has seemed to explain it. When Zero is under a falling ceiling there are times where he is considered next to a wall. At those moments Zero can use this to get a small horizontal boost as well as maintain horizontal speed if he would lose it otherwise. The major application for this is in the Aegis Volcano Base to skip some lava platform cycles through multiple ceiling wall jumps. There's a minor one in the Forest of Anatre to get a small boost from the first falling ceiling was well as not losing any horizontal speed.

Killing ememies with gate transitions

Any enemy still loaded in memory when touching a gate transition will explode and die, counting towards the enemy kill quota. This is used to cut down on slowing down for enemy kills.

Stage by stage comments

This will be broken down to chunks of level groups as they appear in the mission select. The order chosen is considerably different from the other TASes due to what resources and menu routing is done in this TAS.

The level order and brief routing explanation:

Derelict Spacecraft
Mission group 1
- Aegis Volcano Base (obtain Clokkle fast charge speed and Burst Shot for boss fights)
- Oceanic Highway Ruins (swap to fire element and Clokkle)
- Old Residential (equip Burst Shot for non-elemental fights)
- Weapons Repair Factory (swap to ice element for boss)
Missile Factory (swap to fire element for boss)
Mission Group 2
- Frontline Ice Base (unequip Burst Shot for stage and obtain Blizzard Arrow)
- Forest of Anatre (swap to thunder element for boss)
- Twilight Desert (swap to ice element for bosses and equip Blizzard Arrow + Burst Shot)
Area X-2 (obtain Busras for boosting all buster skills)
Mission group 3
- Energy Facility (swap to thunder after mid-boss for main boss and obtain double jump)
- Snowy Plains (swap to fire for mid-boss and main boss)
- Sunken Library (swap to ice element for all bosses until Abandoned Research Lab)
- Giant Elevator
Sub Arcadia
Abandoned Research Lab (each refight section starts and ends with ice element equipped)

Derelict Spacecraft

Enemy kill quota: 19

This is pretty straightforward with slowing down a little bit to take out all the enemies one the way once inside the Spacecraft. I did scroll the screen to spawn an extra Batring to reach the quota. A note about the Batring is that I did have to briefly slow down so it didn't drop to the ground to become invincible. There's also a lot of extra shooting in the stages to manipulate E-crystal drops.

Omega: This fight is pretty straightforward. Just get all the full charge shots to land with the last one hitting as soon as possible. The mistake that I didn't catch until later is that Zero should've been positioned better after releasing the last charge shot for the cutscene.

Aegis Volcano Base

Enemy kill quota: 37

Reaching the quota is pretty straightforward since the Crossbyne rush room gets close enough that getting extra kills isn't that much of a hassle. I do some extra kills at the beginning to manipulate some more E-crystal drops. The lava platforms can have a waiting cycle skipped by doing the falling ceiling wall jumps off of one of them. This is used in both lava platform sections.

The main reason for going to this stage first is the secret disk containing the cyber elf Clokkle. Taking a detour after the Crossbynes rush room takes a chunk of time but the savings for the rest of the game adds up considerably. I also had to wait on a couple of Lamplorts to stop spewing fire to avoid damage as that is part of one of the goals in this TAS.

Blazin' Flizard: Much like the Omega fight I just have to concentrate on getting every full charge buster shot to land though I do manipulate his actions for a bit more variety. Once he's defeated the Burst Shot EX skill and the flame body chip is obtained.

Oceanic Highway Ruins

Enemy kill quota: 23

The mission has a special objective of pressing down each of the four buttons in the stage to lower the water level before Childre Inarabitta's ship destroys them. Every button destroyed loses 5 mission points so even if I was only going for a regular S rank, missing a button is an automatic failure of the goal.

The first half of the stage has a spike pillar that only becomes a problem when pressing the buttons. The only way to pass it without waiting on the ship is the following:

Use a charged recoil rod downwards to pogo above the spike pillar.
Take damage from a Sharkseal X swimming up from below to get i-frames to get around the pillar.

Since using the recoil rod would invalidate the buster only goal and taking damage would also invalidate the goal, I had to wait for the ship to break the terrain to move forward. I do use this time to get the quota for the stage quickly. This did mean that all the work slowing down to manipulate E-crystal drops could've been foregone but the touchiness of the RNG meant correcting that would take a fair amount of work.

Once I did the get the 200 E-crystals needed for the stage, I equipped Clokkle and swapped to the fire element. I did not equip Burst shot because even though it can save time on the Modified Pantheon Aqua the extra lag and invincibility that Childre Inarabitta gained made it an overall time loss.

Modified Pantheon Aqua: This mid-boss has 64 HP. This boss can be sped up with the Burst Shot bit isn't used for two particular reasons. The first one is that the hitbox is awkward enough that I mostly got 7 damage out of the 8 possible with the Burst shot, which meant more shots were required to kill the mid-boss. The second was that due to the effects caused by the mid-boss's attacks would create laggy situations where using the Burst Shot would either start creating extra lag or add more to a laggy situation. Even with regular full charge shots there was still some lag from the attacks I did manage to manipulate.

After the mid-boss it's pretty straightforward with pressing the buttons and moving through while shooting down enemies.

Childre Inarabitta: Using the Burst Shot is not worth it for this fight. Since Burst Shot at this point of the game can only match the damage of a full charge fire buster shot, it would only be slower with additional invincibility frames and lag.

With the standard shot, it's faster to begin the fight with an uncharged buster shot since that has a lower combo level than a full charge fire buster shot, reducing the amount of frames needed on waiting on boss invulnerability frames due to the boss not being next to Zero at the start of the fight. Otherwise it's just some minor manipulation to prevent Childe Inarabitta from going too far away. Once the boss is defeated, the ice body chip is obtained.

Old Residential

Enemy kill quota: 37

This stage has a pretty bad enemy kill quota that requires grinding extra kills. This also has a shortcut that requires a fire attack. Using burst shot would create lag for those situations and another reason it's not used for those scenarios. Burst Shot is equipped for the mid-boss and the main boss of the stage after the first mid-stage cutscene.

Megamilpa: This mid-boss has 64 HP. The mid-boss of this stage has a semi-fixed pattern where it will go through each of these movement once in a set before repeating them:

Arch around, weakpoint on the inside. This can go left or right.
Arch around, weakpoint on the outside. This can go left or right.
Move straight up on one side and move straight down on the other side.

The action of moving straight up takes considerably longer than the other actions though no matter what this move has to happen once. The boss can only be shot twice per action, so while the Burst Shot does create more lag it can take down the Magmilpa in 4 cycles rather than 6 without the Burst Shot. The last movement is manipulate to be an arch around with the weakpoint in the inside to get Zero in a better position when the screen lock is removed.

The shortcut used by the standard TAS and the 100% TAS is skipped here in favor of getting extra kills on the other path since those are pretty quick. The enemy grind is done right before the main boss gates since moving between the two spawn points is fast.

Deathtanz Mantisk: This fight is pretty straightforward with just getting the Burst Shot explosion hits to all connect at every shot. The last shot did create a minor bit of lag.

Weapons Repair Factory

Enemy kill quota: 46

The mission has an extra objective of killing the 4 Eye Cannons in the first half of the stage. This is pretty easy and they count as enemies killed so time is taken out to destroy them. Otherwise there's some slowdown and a Snakecord respawn to meet the quota for the stage. The destroyable junk piles also count towards this quota.

Bee Server: This mid-boss has 32 HP. The Bee Server is only vulnerable when it opens up, which gives enough time to shoot it twice. With the Burst Shot this takes only 2 cycles. The Bee Server also summons Mellnets which count towards the quota, including the ones that die as soon as the mid-boss dies.

Right after the mid-boss Zero swaps over to the ice element for the main boss of the stage. There are conveyor belts in the stage that are ground dashed on when the direction would be faster. A switch is shot at to change conveyor belt directions in a favorable manner.

Devilbat Schilt: The main problem with this boss is that his AI patterns involve invincible teleporting a lot. RNG and position manipulation is used to make sure he never does a teleport to waste time. Once the boss is defeated, the thunder body chip is obtained.

Missile Factory

Enemy kill quota: 41

No stopping to grind out extra enemy kills in this stage needed, thanks to a gate transition getting a number of easy kills before Zero rides the missile. Zero swaps to the fire element midway through the first section. While burst shot is mainly used for the boss, it's also used to get a Heavy Cannon destroyed while wall jumping. Ground dashing is used on conveyors towards the goal since it's faster. The missile section is pretty straightforward though there's a single frame of lag before the last part that falls off that I don't know the reason for.

Crea & Prea: This is the first main boss with 96 HP, shared between Crea and Prea. The baby elves have separate invincibility timers. For this reason burst shot is fired as soon as possible between Crea And Prea to maximize damage.

Frontline Ice Base

Enemy kill quota: 41

This stage also didn't need any enemy grinding to get the kill quota. The first thing done is to unequip the burst shot from Zero since this both makes the boss fight faster and allows for multiple kills with full charge fire buster shots.

Blizzack Staggroff R: Much like the Childre Inarabitta fight this is just about having patterns that allow for consistent full charge fire buster shots on the boss. The snow from the ice beam fired only slows Zero down though some of it is avoided to make sure getting shots to land is possible. Once the boss is defeated, the blizzard arrow EX skill is obtained and is used in place of burst shot for non-elemental mid-bosses and main bosses.

Forest of Anatre

Enemy kill quota: 28

Enemy grinding is done at the very start of the stage with the first Seimeran in the stage. Using a fire attack at the top of the stage doesn't slow the game down and is done just for show. A couple of enemies die at the first door transition. Zero swaps over to the thunder element once the door is reached.

The main gimmick of the stage is to wait on the buttons long enough to allow Zero to successfully get past the blockades. A falling ceiling wall jump is used on the first one since not doing so otherwise would reduce Zero's air speed. I couldn't find a way to get another one on the second falling ceiling, and the other TASes just use the recoil rod to force a block onto the button. A single Tile Cannon and another enemy off-screen from below gets destroyed entering the boss gate transition.

Hanumachine R: The first action is fixed so the only way to get damage early is a full charge thunder shot at the start of the fight. I couldn't get the second attack manipulated so that might also be fixed. The rest of the fight is manipulable so the attacks are changed to ones where Hanumachine R doesn't have invincibility performing the attack. The little monkeys he summons do not count towards the quota, however. An uncharged buster shot is used mid-fight to speed up the fight.

Twilight Desert

Enemy kill quota: 46

At the start of the stage Zero swaps to the ice element for the next 2 and a half stages. Zero also equips burst shot and blizzard arrow. Things are mostly straightforward in the stage though dashing down sand streams going right is faster than air movement outside of running into enemies due to it.

Or Wormer: This mid-boss has 64 HP. This is a pretty straightforward fight though waiting has to be done when it hides back in the ground. There are also PurpleNerples that show up in the fight that can be killed for the quota. They swoop up depending on Zero's vertical position which is manipulated for the ones that show up after the mid-boss fight.

Grinding for extra kills is done at the end of the stage with the two Pantheon Hunters before the main boss fight. The game expects the player to destroy the ones that pop out of the Carrybee G copters but that requires a lot of slowing down.

Anubis Necromancess V: From what I can tell, this boss can retreat into the sand after either certain damage thresholds or hit with certain attacks to do the sarcophagus crusher attack. The crusher attack can be 2 to 4 coffins. I got a 3 and 2 which isn't bad but I couldn't quite get something better.

Area X-2

Enemy kill quota: 32

The moving platforms seem to run on a stage/global timer where some adjustments would mess up the second half of the stage. A lot of slowdown is used to get Gallisni kills when they're summoned by tripping the lasers. Busras is obtained from a quick detour right before the boss door to greatly power up the burst shot's power against fire weak bosses and slightly power up blizzard arrow's power against ice weak bosses. The extra buster power also makes killing enemies faster for quotas.

Copy X Mk II: The big problem with blizzard arrow for this fight is that Copy X will always get knocked back when hit with anything in this fight. Not only is that knockback always away from Zero, Copy X's recoil has a bad tendency to make an icicle shot miss by going over or under him. This is why the initial shot is made to push Copy X towards the right as trying to go to the left caused the bottom icicle to miss. To keep Copy X locked, he was manipulated to either shift elements on the ground or use the slide kick.

Copy X has the ability to heal up 32 HP when at or below half health, so the biggest thing to be done is either to manipulate him to never do it or interrupt him before he actually gets to heal. The latter is what I inadvertently did when Copy X slides to the left. His startup animation for the heal can be briefly seen before his ankle gets hit with a low icicle.

Even though Copy X shifts elements, he is always coded to be non-elemental when attacked. This means there's no reason to switch elements mid-fight.

Energy Facility

Enemy kill quota: 37

This stage in the last mission group since the reward is the double jump foot chip. The maneuverability for the rest of the game vastly benefits from extra vertical options. The beginning of the stage is pretty straightforward. I don't bother with the first half's gimmick of turning on the lights with thunder attacks as it only just moves the Mothjiros towards those lamps rather than taking them out.

The first big circuit breaker-ish structure is activated by pushing in each part with mid-charged buster shots in such a way to hit multiple switches. Then it's on to the mid-boss.

Locomo-IF: This midboss has 32 HP. The weak point is vulnerable for a brief period of time and closes before a second volley of blizzard arrow can dish out its full damage. Despite that it still goes down in 2 cycles. Note that the freezing effect doesn't actually hurt Zero.

After the mid-boss, Zero swaps over to the thunder element and equips Busras. On the way is another circuit breaker pillar that has Crossbynes that's taken out in a similar manner as the first. There's a lot of waiting on Lamplorts and moving platforms that could be avoided with double jump but this is also the stage where it's obtained.

Cubit Foxtar: The main thing about Cubit Foxtar is that there's exactly one move I don't want to happen. She has a move where she will split into 5 big flames and move about for a bit. This move makes her completely invulnerable and should be manipulated to never happen. Otherwise she's pretty straightforward with needing each shot to land as soon as possible. Once the boss is defeated, the double jump foot chip is obtained.

Snowy Plains

Enemy kill quota: 28

This mission has the big Pantheon Base riding hoverboards. Their hoverboards, if something is on them like them or Zero, can destroy enemies and their parts. This is considered slashing damage so one of the Gyro Cannons has their propellers shot off by Zero before a hoverboard hits them to prevent additional hitstop. Hoverboard enemty kills do count towards the quota so the hitstop from those kills work out in Zero's favor. Right before the mid-boss, Zero swaps over to the fire element and equips the double jump foot chip.

Blanc Worm: This mid-boss has 64 HP. The Blanc Worm retreats back into the ground if hit with a fire element attack after popping up. As 2 burst shots can hit the mid-boss per cycle, this takes 2 full cycles and part of a third one to finish off. As the boss can appear on the upper or lower section, the RNG happened to favor the third one on the upper side, leading to a slightly faster kill since the last burst shot can reach the mid-boss quicker.

After the mid-boss the stage is pretty much a straightforward rush to the boss with the occasional slowdowns for extra kills to reach quota.

Glacier Le Cactank: This fight is also pretty straightforward though one of the attacks did create lag. His fist launch attack consists of multiple sprites so the burst shot in conjunction with that attack added extra lag. I thought messing with that attack was amusing so I kept that one in.

Sunken Library

Enemy kill quota: 23

I do not like this mission. Water level cycles, RNG manipulation that's just waiting, and an enemy kill quota that still required grinding out makes for a very frustrating level.

The electrified water does 6 damage to Zero, so even if I wasn't avoiding all damage getting electrocuted would lose a mission point on damage on the spot and ruin a maximum score run. At the very least I spend some of that waiting time on water cycles grinding out extra enemy kills.

Once I reach the corridor before the door checking room I wait a little under 3 seconds for the door RNG to be favorable and minimize movement between doors. I spend that time waiting by shooting burst shots for fun as there's no lag created doing that. Once the check is done Zero swaps over to the ice element and stays that way until the final mission. There's still a little bit of grinding kills on Cannon Hoppers to reach quota before the disk retrieval and boss fight.

Volteel Biblio: This boss always starts the fight jumping up and entering the left hole. He's then manipulated to use his pop-up attack twice since that gives enough time for the remaining blizzard arrow volleys to land as soon as possible with minimal waiting.

Giant Elevator

Enemy kill quota: 73

Despite the huge enemy kill quota, about 50 of that is on the elevator in the middle of the stage. Thus Zero only needs to get an extra 20-ish enemies destroyed to meet quota, though the boss fight has a weird quirk that I'll explain a bit later. All of the extra kills required outside the elevator had minimal to no extra time wasted so those are similar to the regular TAS run without the recoil rod vertical boosts to help out.

The elevator ride in the middle has a gauntlet of enemies that come in set waves. The biggest problem enemies are the shielded Cattatanks. They're only vulnerable when they're in their attack with their mace arm. They don't naturally do that if encountered on the upper level, so Zero has to shoot them once to convince them to do it. They can also be tricked into moving into pits to their demise which is used to speed up some sections if there's other enemies in the way or if taking out multiple of them would otherwise be a hassle. After a set number of waves, the mid-boss appears.

Spearook: This mid-boss has a whopping 96 HP. The main gimmick is that it takes double damage if knocked backwards. There are some attacks that prevent knockback so the first attack chosen avoids any of those attacks. The initial blizzard arrow volley does a small knockback. Zero can follow up with 4 uncharged buster shots to increase Spearook's knockback before charging up for another volley. This is enough to keep the boss effectively stunlocked until it dies.

After the mid-boss is more waves of enemies that are frequent enough to cause some lag with the blizzard arrow shots. It's a messy section but I did my best with what I knew. After the elevator is a straightforward shot to the boss.

Tretista Kelverian: The second part is a very strange mistranslation of "Cerberian". Anyways, he's the second boss to have 96 HP. A big problem is that a number of his attacks makes the blizzard arrow ball miss when trying to avoid damage, requiring doing RNG manipulation before the fight for a good enough pattern. Said pattern was one that started with the shoulder dog launch attack since he just stands still for the most part. Another issue is that the precise area where the blizzard arrow ice ball should be placed to get a hit for full damage is sometimes ambiguous and shifting which means some volleys had to wait a bit longer to get the full hits in.

A small note about the fight is that the dog launch attack adds 2 extra kills for the quota either if the boss dies or the attack resolves. This counts for each use in the fight. In theory this could be used to cut down on slowdowns for extra kills but that's also unreliable. This is how the kill count at the mission end was higher than the mission quota needed.

Sub Arcadia

Enemy kill quota: 37

There's a bit of waiting on a Pantheon Gunner to walk out of the way to avoid damage. Also despite destroying every non-shielded enemy along the way there was still enemy grinding needed to reach the quota.

Crea & Prea round 2: Crea and Prea's got some different moves and still have 96 HP shared between them. They were manipulated to allow for the most shots without waiting. On one of their attacks the third icicle whiffs but that's made up with another shot with an uncharged buster shot worked in to end the fight just a little faster due to attack combo levels.

Abandoned Research Lab

Enemy kill quota: 32

Most of the enemies destroyed are in the middle of the stage between the two sets of boss refights. There's also some waiting on a Shotcounter midway through one of the stages to avoid damage.

A note about the refights is that the text box will not show up until Zero is considered standing on the ground. This does include the breakable box that can show up in the Tretista Kelverian.

For the refights, their elements are arranged in a set arrangement:

| none  |thunder|
|  ice  | flame |

The refights are mostly unremarkable the second time around with a few notes worth mentioning:

Devilbat Schilt required some extra time lost for the last hit since otherwise he'd teleport away and waste much more time.
Cubit Foxtar had a hit that created 90 invulnerability frames rather than 120 when she was shot while doing the weird air flip. It saved time but I'm not sure how consistent that could be used.
Tretista Kelverian's dogs did count an extra 2 kills for the quota so the first Pantheon Gunner in the final section can be skipped in favor of some extra horizontal boosting.

After all that is the final fight consisting of 3 phases with 96 HP each. Don't believe those GameFAQs guides that say the final form has 64 HP since they're wrong.

Golden Omega: This is the intro Omega fight but with an additional sword stabbing attack and extra aggression to the previous attacks. Otherwise it's just the same fight with with more HP to tear through and blizzard arrow to do it.

Fusion Omega: The rest of the phases do not allow for pre-charging the buster during the cutscenes so the first shot landed is an uncharged buster shot. Otherwise it's making sure that Zero is able to use blizzard arrow volleys on this form as soon as the invulnerability runs out.

Omega Zero: The mirror match is a real pain to optimize blizzard arrow shots for. Every hit that lands when Omega isn't attacking causes knockback. This knockback is dependent on where he's hit, similar to Zero. This leads to the problem of misplaced shots having the icicles or the ball miss. The other concern is that distance from Omega is the only really big influence on his attack pattern manipulations. His ~~Raging Storm~~ Rekkkoha is avoided since that has an invincibility period that lasts longer than the invulnerability frames from being hit. His dash into ~~Split Heavens~~ Ryuenjin can be baited out and ended earlier to get into position for damage.

The last cutscene has a mandatory use of the saber by Zero required to reach the ending. This doesn't count against the in-game unlock for the buster only S rank reward.

Possible improvements

Known improvements
- I didn't move into place for the cutscene after the intro Omega fight. I wasn't sure if that would lead to RNG changes down the road so I left it where it was.
- There's one part of the Aegis Volcano Base where I didn't need to do an extra wall jump to get higher horizontal speed. I didn't notice that until much later. Fixing that would mess with the RNG due to wall jumps affecting that value.
- Rerouting the E-crystal route with the conditions I set for myself meant that the first half of the Oceanic Highway Ruins would be a better place to manipulate a majority of the crystal drops before the mid-boss. However, any future attempts at this would probably be fine foregoing the "no damage" condition altogether if they so wish.
- I could have less lag in the first Glacier Le Cactank fight by having another attack but I left that in since I found the movement I did amusing.
This is surprisingly the second TAS of any of the Mega Man Zero games to route out a maximum mission score TAS so the enemy routing might be improvable in ways I didn't consider.
The Giant Elevator gauntlet in the middle of the stage could have a better handling of the enemy waves that I didn't see, or at least handle without generating any lag.
I decided my buster route with the plan of minimizing extra menuing but there's the possibility that swapping over to a non-elemental body chip and using the reflect laser could speed up some sections in the last third of the TAS. This could also involve adding in the quick charge head chip from the Snowy Plains for additional use of the hidden combo for 50% charge speed reduction.
Some of the boss fights with the blizzard arrow feel like they can be improved in spots, especially with Tretista Kelverian.
The weird hit on Cubit Foxtar that only had 90 invincibility frames has potential to save some extra time if exploited more but there's not guarantee that would work out overall.
There might be some extra movement optimizations that I may have overlooked here and there.

Special thanks

hellagels and Geinuhayst for their current Mega Man Zero 3 publications
Xaphan, computerbird, Rolanmen1, and McBobX for their submissions for Mega Man Zero 3
mech_gouki for their GameFAQs guide detailing the specifics of the attack combo level system
Shadow2099 for their GameFAQs guide for the rank requirements across all the Mega Man Zero games
All the other folks who have contributed to the Mega Man Zero TASes on TASVideos one way or another

Extra notes

For my personal encode I used this input file:

UserFiles/Info/638117409522911950

This doubles as a verification movie for Hard mode if any future TASers want to tackle what is essentially a New Game- mode with more damage and less options.

Suggested screenshots

Frame	Screenshot
Frame 32412: Zero feeling a little spicy.
Frame 77666: Pale moonlight not required.
Frame 87308: Zero give the top enemy a surprise.
Frame 125168: Zero shows Copy X his buster skills.
Frame 171466: Cleaning up the elevator.
Frame 220423: Whiff punishing with an icy volley.

feos: Claiming for judging.

feos: Verified the achievements, and since this goal is rooted in the in-game mechanics, entertaining, and feels different from other branches, I'm accepting it to Alternative.

despoa: Processing...

Submission #8026: Darkman425's GBA Mega Man Zero 3 "Z-Buster only, maximum score" in 1:03:56.27

Submission Comments

Important note

Introduction

Run notes

Mechanics and techniques

Stage by stage comments

Possible improvements

Special thanks

Extra notes

Suggested screenshots