anyone ever get screwed over by a trade?

Among the passerbys I caught a guy who said he had diance, I invited him to trade.....end of the story he screwed me out of 2 legends, by offering a pokemon named "2legends4diance"
I was pretty stupid to go along with it, but I registered him as a friend....he invited me to game chat and did an evil laugh several times

oh well, good thing I had cloned them before I transfered them to XY :'^)