This happens if a save operation was interrupted, a cartridge contact failed, or a hex edit broke the file structure.
The Nintendo 3DS manages save files differently than standard PCs. The system stores your progress inside the SD card using unique title IDs. Digital vs. Physical Cartridges project x zone 2 save file
For a full cartridge backup, you can use GodMode9 to dump the raw save file directly to the /gm9/out/ folder on your SD card. Clear Save and New Game+ Benefits This happens if a save operation was interrupted,
On a physical 3DS console, save files are encrypted and tied to your system's SD card. Digital vs
Carrying over save data from the or having a clear save from the previous game grants specific in-game rewards: Achievement Reward Item Description Demo Clear (1x) Lesser New World Equipment item for the full game. Demo Clear (2x) Urashima’s Special Anniversary Badge Accessory for stats boost. Demo Clear (3x) Urashima Special Wooden Sword Bonus weapon for early game. Demo Clear (4x-10x) 1,000 Gold (each) Currency for purchasing upgrades.
Do not mix save files from drastically different game versions. If your cartridge has a different update patch (e.g., ver 1.0 vs ver 1.1), using a mismatched save file may lead to weird side effects or "corrupt data" errors.