You cannot find Mew, Celebi, Jirachi and Deoxys in Pokémon Ruby. Mew, Celebi, Jirachi and Deoxys are event-only Pokémon. Jirachi was available on the pre-order disc for Pokémon Colosseum that would allow you to download Jirachi from the disc over to Pokémon Ruby.
I believe you can find any Pokemon in the Dream world, except the Pokemon acessed by Nintendo events prior to the make of these two games, such as Mew, Celebi, Jirachi, Deoxys, Manaphy, Phione, and other very rare Pokemon.
You have to complete the story mode then catch deoxys, celebi and mew.
Mew
A Pokemon Center is where you go to heal your Pokemon when they are injured. You also go to a Pokemon Center to look a the Pokemon you have caught, via the computer. Hope this helps. :)
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the Unobtainable Pokemon in RSEFRLG are Celebi, Mew, Jirachi, Deoxys, and 000 (Missingno. ( DO NOT ATTEMPT TO CATCH))
You can catch Groudon,Rayquaza,Latios,Deoxys,Celebi,Jirachi,regiice,regirock,registeel,and Mew
In an Event. The same way to get MEW and CELEBI
you want the hack Pokemon go get action replay
jirachi i got him maybbe celebi as if you have it you can get mew
It is one of the event only Pokemon like Mew, Celebi, Deoxys, Jirachi, Meloetta and Genesect.
You can trade for them. That's all I can say.
Its going to be in late November from what Ive heard. Because there is a pattern if you didn't notic, jirachi, mew, celebi, deoxys . See? so there Will most likely be an event in late November
In emerald you can catch deoxys and jirachi but your internal battery needs to be working if it is keep going to the space center until they get to rocket launch 99 then talk to the dude that tells you which one there on and he'll ask if you would want to go on 100 if you do you can catch jirachi and deoxys if not you can catch celebi the same goes for ruby and sapphire hope this helps
I would say Groudon or Kyorge or deoxys or Jirachi or mew or mewtwo or rayquaza
No, Deoxys is only in Emerald, and you need to migrate it to can catch it. As for Celebi and Mew, you need a cheat code for them.
You cannot catch Mew, Celebi or Mew in any Pokémon games however you would have been able to get Jirachi provided you had pre-ordered Pokémon Colosseum and received the pre-order bonus disc which would have allowed you to download Jirachi to either Pokémon Ruby or Pokémon Sapphire. Jirachi can also be obtained from early version of Pokemon Channel for the Gamecube upon completion of the main story.