Including the event only's here are the legendaries in emerald: Latios/Latias, Kyogre, Groudon, Rayquaza, Deoxys, Regice, Registeel, Regirock, Mew.
all the legendaries and how to get them here http://www.psypokes.com/emerald/legendaries.php
go to this page http://www.serebii.net/diamondpearl/legendaries.shtml this page has all the legendaries you can normally catch in in Pokemon diamond/pearl all other legendaries you have to transfer from a 3rd generation game
Here are all the legendaries you can get without cheats: Groudon, Kyogre, Regice, Regirock, Registeel, Rayquaza, Latios/Latias.
if you don't have that Pokemon just catch it and evolve it
Catch all the pokemon.
g;r;g;g
You cannot catch all the pokemon in emerald. You much catch the maximum for that game, and trade or cheat in the rest.
To catch every Pokemon, you need action replay for the few last diamond legendaries. You will need Pokemon fire red/leaf green and emerald. Migrate them to Pokemon diamond. In Pokemon diamond, fill up your pokedex by catching Pokemon normally or with poke radar, or use gts. It will take a long time to catch all Pokemon
YES!!!!!!!! all you have to do is see all the Pokemon and catch the ones you can catch in the game!!!
I put a link to guide on all the legendary pokemon in Pokemon Black in the related links.
No you just need to SEE all the Pokemon in emerald pokedex
no but if you catch all the hoenn pokemon you can catch jotho and kanto pokemon