Without this update, your game remains at (base cartridge or dump). Many custom ROM hacks (like Pokémon Ultra Sun & Moon - Photonic Sun/Prismatic Moon ) require the v1.2 update as a base before patching.

For fans of the Alola region, Pokémon Ultra Sun and Ultra Moon represented the pinnacle of the Nintendo 3DS era. Nearly four years after the release of the Nintendo Switch, the 3DS’s online servers were officially discontinued in early 2024. This event has sent ripples through the modding and homebrew community, forcing players to rely on local files—specifically (CTR Importable Archives)—to keep their games updated.

You cannot receive the latest events or Mystery Gifts without being on the latest version.

If you previously attempted to update Ultra Moon through the Nintendo eShop before its closure, or if a previous CIA installation failed midway, a broken update "ticket" may be stuck in your system memory. This prevents any newly installed update CIA files from overwriting the slot. 3. Broken "Game Patching" Settings

Q: Is the Update 12 CIA Work safe to install? A: As long as players download the CIA file from a reputable source, the Update 12 CIA Work is safe to install.

As of 2026, the 1.2 update remains the final and latest version for Pokémon Ultra Moon . While official servers are closed, custom servers like Pretendo may eventually support these games. Having the 1.2 update installed via CIA ensures maximum compatibility with such custom server solutions.