I'll get straight to details. I wanted to create and edit a few Pokemon for fun on my physical copy of Pokemon Sun. I decided that PKHeX would be a good idea, so I followed a few videos and got it downloaded. I started to mess around with it a bit, and I successfully got a few Pokemon on my save.
I went to bed, and the next day I decided to actually begin creating Pokemon that I wanted, so I filled up a few boxes. I made sure they were legal, but they were legendaries that would be difficult to get, like shiny Gen IV legendaries and such. I also hacked a few copies of shiny evolutions. I made a backup of the vanilla save, then saved the modified save separately and turned on my game. When it booted up, it displayed a picture and a block of text saying
"The saved game data is corrupted.
Please go to the home manual and refer to the manual for this software."
I switched the save to vanilla and started it up and it worked. No data was lost except the Pokemon I wanted to hack in. I decided to test it more, and filled up a box with otherwise normal Pokemon, which were shiny and Lv100. Turned it on, corrupted, switched the save, it was fine.
I looked into it a bit online and found that there was a bug where the save file would corrupt if you were in an area with a PC. Everyone said it was patched, but for safety's sake I moved my character from the nursery to Route 6 directly below it. I hacked in 6 Charizards, still no avail. At that point, I took the save and put in a very simplistic, normal shiny Eevee. No other changes, just this level 1 shiny Eevee. Same message as all the times before.
I looked around more and everyone either attributed it to the bug, or didn't have an answer, so that's when I typed this as a last resort.
For information, I have an old 3DS and a physical copy of Sun, which according to the game is at v1.1. I use the Soundhax Homebrew v1.1.1 and JKSV, as well as PKHeX (20170318). If you need any more information, I'll reply with the info I can gather.
Thank you in advance for your help!
