: Use a tool like WinRAR or 7-Zip and select "Extract" on only the Part 1 file.
Yo-kai Watch Blasters: Update 2.4 3DS [Moon Rabbit ... - Ziperto
Because many 3DS games are large, sites often split them into multiple parts (e.g., Part 1, Part 2).
: The extraction software will automatically detect and pull data from Part 2 to create the final single .cia file.
: The game was later updated with the free "Moon Rabbit Crew" expansion, which added new missions and playable characters. How to Use Multi-Part RAR Files