Jirachi can be obtained through the Bonus Disc from Pokemon Colosseum. You'd need to connect a Gameboy Advance Link Cable to the Gamecube with the Bonus Disc playing. Make sure Pokemon Sapphire, Ruby, or Emerald is in the Gameboy Advance, then transfer Jirachi to one of the boxes in Ruby, Sapphire, or Emerald. Celebi can be obtained using the Japanese Bonus Disc, which requires a completed Pokemon Colosseum save file, but the transfer is the same. Currently, Nintendo events are the primary source of getting rare Legendary Pokemon for Pokemon X, Y, Omega Ruby, and Alpha Sapphire. You can participate these events either by visiting a local game store or downloading the Pokemon from the internet.
You can't.
use a bunch of rare candies.A LOT.
you cant dumb dumb
there is no way to get 999 rare candys without gameshark or action replay.
You cannot get infinite rare candies without hacking and cheating. There is a set number of rare candies available in the game. The only way to get infinite rare candies is to hack and cheat.
You just have to find them
01287ccf - rarecandy
use action replay. HAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA HAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAyour an a s S hole. HAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
No, you can't I recommend saving your game before battling rare Pokemon or legendaries.
Depending on rare, there are actual rare Pokemon and Legendaries. There is a rare Pokemon about in every location and what I mean is by the low encounter rate. Legendaries can be found by certain interactions in different places. I suggest using Bulbapedia, Serebii, or Azurilland to find these Pokemon depending on the game you are playing, for some "rare" Pokemon can be common in other games.
You can't unless you're planning to go underground ALOT.
By using game shark codes