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"3DS World" generally refers to community-driven databases, archival sites, or regional formats. In the context of updates, Pokémon Ultra Sun was released globally, meaning update files are often classified by region (USA, EUR, JPN). Ensure your Update 1.2 CIA matches the exact region of your base game, or the console/emulator will fail to recognize it. Going Portable: Emulating Ultra Sun on Modern Handhelds
CIA files are used on the Nintendo 3DS to install games and content that have been downloaded from the Nintendo eShop or extracted from cartridges. A CIA file essentially contains data that can be imported directly into a 3DS, allowing users to play games or add content. pokemon ultra sun update 12 3ds world cia portable
Fixes a game-crashing bug triggered when using specific moves like Plasma Fists or Ion Deluge in competitive or casual battles. Going Portable: Emulating Ultra Sun on Modern Handhelds