Introduction
Metroid One Zone is a ROM hack of Metroid: Zero Mission developed by DuoLa Ayu. The hack was developed in 10 days mainly as a demonstration of the MAGE tool's ability to modify Metroid: Zero Mission, but the developer refined it further into a compact but polished standalone hack. This hack was released on 1 April 2025 where the main joke (I guess, kinda?) was that the Easy mode was designed to troll exactly one person in the Metroid Construction community while the other two difficulties are proper play experiences.
I tried this a day after April 1st and really liked playing through the hack on all of its difficulties. I then tried doing the fast route on Normal and wanted to see how it'd look as a TAS. Mainly this was just an excuse to try out Metroid: Zero Mission TASing since the "any% Normal" route is both really short and straightforward that it made for a good learning experience while not needing extensive routing like a 100% route.
Game notes
- Emulator used: BizHawk 2.10
- A small bit of RNG manipulation for missile drops
- Plays on Normal mode
- In-game time: 0:02:27
- Item completion: 15%
- Only fights Deorem the Charge Beast
- Also skips what are probably 2 items that were intended to be mandatory
Difficulty choice
It could be inferred by the introduction section but I should make it more explicit. Each difficulty mode in Metroid One Zone has unique progression.
- Easy mode is an obvious joke difficulty where the game replaces the normal Power Grip room with an elevator leading to a unique area with all of the items placed in easy to obtain areas. There's not even any proper bosses to fight outside of Deorem the Charge Beamst at the beginning.
- Weirdly enough I'm pretty sure this is also the only difficulty with permanently missable items (one Energy Tank and the Charge Beam) due to the doors locking once Samus goes through the first red missile door.
- Normal mode is the main experience where Samus has to explore around a compacted map and find items in an unusual order. Kraid and Ridley can be fought but are optional fights.
- There is a developer intended route to complete the game in about 5 minutes of in-game time via sequence breaking. This mainly involves taking passages that a first time player will only notice when going through them later following normal progression.
- This difficulty doesn't actually have any unique areas to itself, interestingly enough.
- Hard mode is an unlockable difficulty with a completely unique area accessible via an elevator where the crumble blocks next to the Morph Ball would normally be. This difficulty expects the player be familiar with both wall jumping and the map layout of Normal difficulty to complete.
- Ridley is a mandatory boss fight on Hard mode to access the rest of the map, as the Plasma Beam is also required to reach the ending. Kraid is still optional.
Due to the differences between difficulties, I feel that the difficulty is needed for the branch name.
Routing notes
Start to Missile Pack
The Ice Beam below Samus is required on all difficulties to reach the upper part of the room. The right wall is just too high to wall jump from at the normal jumping height without using the rippers as platforms. After grabbing the Ice Beam, going up the left side is faster due to less horizontal movement needed. A little bit of waiting is needed to use the rippers as freezable platforms. From there it's pretty straightforward path through the crumble blocks to the first Missile Pack of Easy and Normal mode.
Charge Beamst to Morph Ball
Shortly after the Missile Pack is obtained Deorem the worm is fought. An enemy that chases Samus is destroyed in the arena, timed to drop a missile refill to be used later. Deorem is taken out by landing three missiles on the eye on the same frame for a one cycle. Charge Beam isn't required so Samus immediately jumps down the hole to the left of the fight. There's a red missile door to the right after the hole with the Power Grip in the room beyond. The Power Grip is required to reach the Morph Ball as once again the ledge is too high to wall jump from. Once the Power Grip is obtained Samus once again has to move up to get to the room with the Morph Ball.
Going around for the Hi-Jump Boots
Taking the right passage from the Morph Ball leads to a big room with two paths on the right. The bottom path is taken first as the top path is currently blocked off.
Well, well, well, if it isn't the- nope, gonna stop myself there. This room is locked until both of the guardians are destroyed. The top one is made to hop through the small opening made via shooting the floor below. The 3 missiles taken into the room are used on the first one to destroy it faster. A little bit of RNG manipulation is used to force it to drop a couple of extra missile drops so 4 missiles could be used on the walking guardian found on the lower section of the area to speed up destroying it. Once both are destroyed Samus moves to a small vertical shaft.
I assume the next "intended" any% item is the Super Missile pack by taking the lower left exit in the vertical shaft but it's skipped in this TAS. Instead the upper left tunnel is taken to return to the starting area. From the starting area, the Power Grip and Morph Ball are used together to traverse a small tunnel on the left for the Hi-Jump Boots. The jump height boost is needed to access the final upper area of the map later.
Power Bombs before normal Bombs, much like an SM Rando
After the Hi-Jump Boots are obtained, Samus goes back but intentionally falls through the crumbling block path just outside the Hi-Jump Boots room. Down below is a hidden Morph Ball tunnel to a large room. What I assume is required is that the player needed to obtain the Super Missiles to open up a passageway on the left side. That passageway leads to the activator for the moving rails, which are required to reach the Space Jump upgrade. The Space Jump is then normally needed for the Power Bomb pack found in this room past the rows of crumble blocks. However, with frame perfect jumping it's possible to obtain the Power Bombs found in this big room without Space Jump. This is what the TAS does to save a good chunk of time. After obtaining the Power Bombs, Samus enters Morph Ball to move back through the passage back into the first area.
Heading out to the end
Now that the Power Bombs are obtained, Samus moves back up to the passageway right of the Morph Ball. From the room beyond the upper path is now taken. A Power Bomb is used to break through a bombable floor in the Spazer Beam room. Samus then jumps up through the opening that requires Hi-Jump Boots to reach the final area. From there it's a straightforward path through the hidden tunnel on the right and moving up into the hangar area where the ending sequence is initiated by jumping into the Space Pirate ship.
Potential improvements
This is my first time TASing anything Metroid: Zero Mission so there might be some small optimization movements that could be found, mainly the wall jumping. Otherwise I personally feel that this is solid enough for me.
DrD2k9: Looks good. I agree with the branch naming logic. Accepting.
