Mega Man Zero 4 is the final game of the Zero subseries, and we finally get to see these "humans" that the X and Zero series have been talking about constantly. Oh, and Dr. Weil's back. He's still crazy.
Not as much collecting this time: there's only one Cyber-elf! However, there are a lot of head/body/leg chips to create, so get to enemy farming!
Two unused buttons that were not translated for the American and European versions. They translate as "Back" and "Close".
Preliminary
Final
These buttons would have been used on the Elf Menu. They were likely removed because it was easier to just use B to navigate through the menu, and removing them gave room for two more lines of text. There was really no reason to keep them, so out they went.
Animation group 517 in the Collection contains an odd looking sword. It is next to weapons and projectiles used with the Z-Knuckle. Given that it does not fit the art style of the rest of the game, it may have been taken from another project and used as a placeholder.
Watch on YouTubeThe Prologue and Credits music tracks lack vocals in the international versions. The Japanese ending theme is used in all versions of Mega Man Zero Collection & Zero/ZX Legacy Collection, even in English.
There is however an unused track for Zero 4 in Zero Collection that could be the international version of the ending theme, but the first part where the singing was originally edited to remove vocals is very unfinished (nearly no instruments).
When most enemies are destroyed with a non-Buster weapon in the Japanese version, a viscous crimson goop flies out of them. Like theothergames in the series, this was removed from the international versions.
As Dr. Vile's name was changed to Dr. Weil outside of Japan (due to the name Vile already being taken in the west by the Mega Man X character known as Vava in Japanese), the icon was changed from a V to a W.
Unsurprisingly, the Japanese 4 wasn't used for this.
The European version continued the region specific logo used in the previous twogames, although it looked jarring against the background art. The menu and difficulty selections are also positioned differently in each version.
Additionally after pressing the start button, the copyright notice on the bottom of the screen is still visible in the Japanese and European versions, but disappears in the US version, presumably due to the US logo being slightly bigger than the Japanese one and the aforementioned menu and difficulty selections (when a saved game if present and if any Mini Games are unlocked, in addition to having both Hard Mode and Ultimate Mode unlocked) being too low for the copyright to show. All of this was reverted in the US version of Mega Man Zero Collection however.