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Replacing horn attack with horn drill in pokemon red. (If you know, you know)

killing a shiny on accident

mine was i acdentaly made my zamazenta in pokemon sheild forget a move that i cannot bring back

oof

not me but my brother once reset his game with a shiny charmander because it was female

I killed the second Koraidon you can catch in area 0 and had to close my game to get it back, which made me lose a bunch of progress. Two of the worst things I lost were a Walking Wake and a bunch of rare candies I had saved up from Tera Raids.

Using my master ball by accident on a eelektrik