Metroid Zero Mission

Metroid Zero Mission is Samus' first mission, retold in a Super Metroid style with 80% more anime.

Unused Features
The ability to toggle equipment on and off, just like in Super Metroid. It may have been used for debugging purposes, however, prototypes of Metroid Zero Mission have an accessible debug menu on the status screen in a similar fashion to Metroid Fusion. From the debug menu, any ability can can be toggled on or off, regardless if you have obtained it. While you can toggle abilities with this Super Metroid like feature, you can only do so once you obtain the ability. Having a second, separate method, to toggle equipment on or off just for debugging purposes is redundant and lends credibility to the idea that the developers intended for the player to toggle equipment like in Super Metroid. The most likely reason why this feature was dropped was because there isn't a real reason to allow the player to toggle abilities on and off. In Super Metroid, you could toggle abilities to create beam combos but that feature doesn't exist in Metroid Zero Mission.

You can enable this feature with the CodeBreaker code. This function only allows toggling beam upgrades and upgrades in the Miscellaneous category. A ROM hack was created to allow toggling any upgrade.

Testing Rooms
Much like Metroid Fusion, test levels have been discovered. They do differ from Fusion a bit. The jewels from Wario Land 4 are used as a water effect layer in one room.

Unused Graphics
The graphics used by the disabled item switch feature.

Placeholder graphics for the expansion items that get replaced with animated versions.



The testing room tileset contains blocks that resemble very crudely-drawn expansion items. The ones without an icon in the top-left corner were recreated from the 8&times;8 tiles. Like in Fusion, leftover blocks from Wario Land 4 are present.



The graphics data for the Metroids has a scratch area, showing how it should look assembled. There is also a useful number guide for the electrical effect's animation order.



The graphics for Zero Suit Samus' auto-charging stun gun has a placeholder graphic for the Charge Meter that appears in the HUD. The meter graphics are dynamically loaded from ROM.



Present in both Fusion and Zero Mission, there exist in the font graphics unused L and R button icons, and several different versions of the capital X character.



Also present in both games is this placeholder graphic, with Japanese 「マップ」, meaning "Map", on it.



Found only in Zero Mission is this tile with "GEKI TAI MACHINE" written on it.

Crocomire


Crocomire, a sub-boss from Super Metroid, was set to appear in Zero Mission! Unfortunately, the sprite's coding is extremely incomplete, and does little more than run the idle animation and take damage. A ROM hack exists that turns Crocomire into a fully-functional boss, demonstrated in the video below.

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Unused Track


A leftover track from Fusion, which was used in that game's opening.

Intro Subtitles
The large opening text is always English. Accordingly when set to English its subtitles aren't used.