The official Mega Man Zero series concluded as a tetralogy on the Game Boy Advance. Following Zero’s ultimate sacrifice in the fourth game, the narrative timeline officially jumps forward to the Mega Man ZX series. Because Capcom and developer Inti Creates designed the fourth game as the definitive end for the character, no official "Zero 5" ROM exists. Notable Fan Projects and ROM Hacks
Because fans were left wanting more after the series ended, several "Mega Man Zero 5" projects have emerged in the community: megaman zero 5 rom
: Another high-profile fan project. While the developers have experimented with test ROMs for the Game Boy Advance, they have stated that the final project will likely be a standalone PC/mobile application to avoid the technical limitations of the original GBA hardware. The official Mega Man Zero series concluded as