You can't trade Jirachi in the Global Trade System(GTS) because It will say that Jirachi is a Special Pokèmon and It will not let you trade it . I tried and It said It's a special pokemon.
B
BenQD86
well, if you'd like the proof. lol i also traded a Kyogre. And I've traded event pokemon in GTS before. it has to be for other event pokemon if memory serves. And the Kyurem i have does have a nature Kyurem doesn't normally have. Of course, there is also the off chance it was a non-event Jirachi (i.e. Action Replay made.) Had that happen before. lol Couldn't use it in batle online (Pinsir was that pokemon.)
