This is a question from this link on GameFAQs.
> I've been cloning a lot via the trade method where you turn off a
> Anyways, today I was swapping items for a team, and I realized, hey!
> one of my items is missing. At first I was thinking that I had
> accidently tossed it or traded it away. Upon further inspection
> however, it appears as though my items have reset to an earlier point
> in time. Pokemon had items equipped that wasn't what I last left them
> with. Several items I had gotten in battle maison recently were gone.
> Also my BP I had obtained and spent was back again.
> So it seems although my Pokemon were there, item data was possibly
> corrupted and reverted to an earlier point in time. Or something like
> Anyways though I was able to buy the missing items back. But it's
> definitely gonna make me think twice about cloning with this game.
> Thankfully i've already purchased another game for such things.
This is the reply by smith 433 which says that it can corrupt your game
That is one of the risks that I was trying to tell everybody early on
as I helped to spread the method on the trade board. You are trying to
time the power off cycle between a trade success communication and the
unit saving the file. It is rare but it is possible to hit it at just
the right moment as it starts to save.
All of the cloners on the trade board act like cloning is a no risk
procedure. They may eventually get surprised by a corrupt file but
more often than not, they end up deleting a Pokemon to be cloned
despite doing everything correctly. It's rare that this happens, but
it can and does happen.
I have no problem with cloning (as I said I was one of the first on
the trade boards who taught others), but I do have a problem with
cloners not telling people about the potential to lose their Pokemon.
The way I see it, everybody should be at least made aware that it can
happen even to the best cloner as long as they are using the trade
I am glad that you didn't lose your entire file. Maybe you can help to
continue to spread the word too.
Also, according to this wikiHow page on cloning Pokemon, it says that it can harm your save file.
- Although there is no proof yet, there is a small chance your game can get corrupted. Do at your own risk!