Go to birth island.
Cheat to get the aurora ticket then go to birth island.
There are sadly no special events to catch Deoxys in Sapphire. You HAVE to trade a Deoxys caught in an event from FireRed, LeafGreen, or Emerald.
You catch deoxys at birth island.
The Attack version Deoxys can be found by completing the puzzle on Island #9 in Fire Red only. The Defense version Deoxys can be found by completing the puzzle in Island #9 in LeafGreen only. -jean- >w<
I'm afraid you can't. Although if you have a friend that has it on emerald, firered, or leafgreen you can get one by trading. Good Luck!
Deoxys defense form is found in leafgreen.
You can't find one you need to trade one from FireRed/LeafGreen/Ruby/Sapphire or Emerald
Where you catch Deoxys
Get a Deoxys in Pokemon Emerald, Ruby, Sapphire, Firered, or Leafgreen using the Mystery Gift, and migrate it to your Diamond Version.
You don't get a Shiny Deoxys from a man. You'll need to get Deoxys in Pokemon FireRed, LeafGreen, or Emerald. It is extremely hard to get a Shiny Deoxys.
Go to birth island.
you have to get it in a event and you cant get it in Pokemon leafgreen or firered