Go to birth island.
You catch deoxys at birth island.
Pokemon Emerald: Birth Island Pokemon Sapphire: Trade from Pokemon FireRed, LeafGreen, or Emerald. Pokemon Ruby: Trade from Pokemon FireRed, LeafGreen, or Emerald.
Get the aurora and mystic ticket by going to a Nintendo event.
Cheat to get the aurora ticket then go to birth island.
you need to migrate from emerald or firered/leafgreen where you can get him from birth island
About 16, if you found the hidden cave in the mansion (that leads to Birth Island) about 44. Btw, on Birth Island you can get Lugia and Ho-Oh
You must get a ticket from a Nintendo Event that takes you to Birth Island.
You can't go to the island unless you have the aurora ticket which is now impossible to get without cheats, with that show the sailor who takes you on the ships he will take you to Birth Island.
you have to have a ticket to birth island and solve the triangle puzzle
No there are 9 islands, 0ne, two, three, four, five, six, seven, birth island, navel rock which is an island.
Go to Vermilion then show the guy on the dock your ticket, then go to birth island