In Poke'mon Emerald if you have ever played, you know about the
Sky Pillar. The Sky Pillar has Rayquaza in it, but you may not have known this: in Poke'mon Ruby/Sapphire there
is a Sky Pillar. It is the say deal as Emerald, just drive your bike over the cracked tiles to get to Rayquaza. Oh yah, another thing it is in the same spot as in Emerald and you can only get to it after you defeat the Poke'mon League.
Hint:
Instead of using the Master Ball on Groudon/Kyogre save it for Lv70 Rayquaza, but still bring Ultra Balls if you want to save it to trade into a different game.



