Groudon is in emerald, it can be caught with a master ball, which can be found at team aqua's hideout just off of lilycove city.
you need Pokemon emerald pass all rare candies
when you see all the Pokemon in Pokemon emerald go back home and talk to professer birch. he will let you pick 1 of 3 very rare Pokemon.
there are 6 tiles where feebas can be caught its super rare so it will take a long time.be patient, you will find it i have a milotic in lv100.its all worth it. but you need a super rod so good luck.
yes you should start over in Pokemon emerald cause you may forgot all the other rare Pokemon if you completed the game you should restart it or you will just be bored of it
link together with all activates the mystery gift
Groudon, Kygore, Rayquaza, Regice, Regirock, Registeel, Latios/Latias.
you can use it anywhere if you have an AR
Rayquaza, Banette, Claydoll, Sableye, Zubat, Golbat. They're all above lv30
one word: cloningUse cloning to clone rare candies (clone Pokemon while it's holding a rare candy) and use them on your Pokemon.
get all the Pokemon in the emerald dex
emerald has all the Pokemon
200 Pokemon is all the emerald Pokemon to get more beat elite four and get national dex