POKEMON EMERALD UNLOCKABLES
Deoxys
Like previous games, Deoxys has its own form in this game. It is the Speed form. It can only be found on Birth Island. The Aurora Ticket is required.
Ditto
You can catch Ditto, but only after beating the Elite Four. Go to the Desert Underpass. It is only in the middle.
Groudon
Go back to the weather institute. Talk to the man again. He will tell you where Groudon is found. You might need HM03 Surf. Go to the route where he is and go inside. You will find Groudon in the Terra cave. To get groundon/kyougyr trade from ruby/shapire
Ho-oh and Lugia
Get the Mystic Ticket, then go to Navel Island.
Jirachi
To get Jirachi, you need a Gamecube and the pre-order version of Pokemon Colosseum. Then, trade it to Pokemon Emerald.
Kyogre
Defeat the Elite Four, then go back to the weather institute. This is where you got Castform. Go upstairs to a researcher who studies patters of weather. He will tell you where Kyogre is found. You need HM03 Surf and HM07 Dive. Surf on the route you are supposed to until you find a location to dive. Once you get to Kyogre in the Marine cave, get in front of him. Use Net Balls on him.
Latios or Latias
After defeating the Elite Four, watch the television downstairs in your house. Mix your records with a Pokemon Ruby or Sapphire with the Eon Ticket. Then, go to Southern Island.
Meowith
Go in the building to the left of the Battle Tower. Give the woman a Skitty and she will give you a Meowith with Retro Mail. The higher the level of your Skitty, the better the Meowith, which means you can get Persian faster.
Mew
The only way to get Mew in the game is by getting the Old Sea Chart. This is an item that is only available through a special event outside the game.
Rayquaza
Go to Sky Pillar. When Groudon and Kyogre are fighting, he wakes up and stops the fight. Once you have done that, go back to Sky Pillar to find Rayquaza. You can get to Sky Pillar by going to Pacifidlog Town. Go right until you see a crack in the sea. Go into it. REMEMBER: Use a Master Ball on it.