If you are using a modified 3DS or an emulator like , you can install the update as a .cia file.
In the labyrinthine world of 3DS homebrew, few phrases carry as much weight for Pokémon fans as “Pokémon X v15.0 – World CIA – Region Free.” To the uninitiated, it’s a jumble of jargon. To a veteran using custom firmware (CFW) like Luma3DS, it represents the holy grail: the most stable, complete, and accessible version of the 2013 classic.
: This update inherited critical fixes from earlier patches (v1.1 through v1.4), such as the infamous "Lumiose City Bug" which could corrupt save files if the player saved in certain areas of the city. PocketMonsters.net File Formats and Installation
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