All of the legendary dogs: Rakou the god of speed Entei the god of power
suicune the god of recovery are all Johto Pokemon not hoenn.
You can only capture Raikou in pokemon leafgreen and firered version you can also snag a shadow Raikou in pokemon colosseum.
you dont
catch it in the wild
You can't.
You can't. You have to trade it from fire red or leaf green.
You can't catch one in Pokemon Emerald.
Yes, You can catch Groudon in Pokemon Emerald.
No you cannot catch Entei in Pokemon Emerald.
You can't catch a Bellsprot in Pokemon Emerald. You trade it from Pokemon Leafgreen!
There are many Pokemon you catch that are similar in sapphire and emerald but there are many Pokemon emerald can only get and not sapphire.
Cressilia is a 4th generation Pokemon so you can't catch it in Pokemon Emerald.
You can't catch or obtain other trainers Pokemon in emerald.
You can catch Mewtwo, Suicune, Entei, Raiku, Ho-Oh, and Lugia.