for emerald, raquaza, groudon, kyogre, your starter pokemon, magnemite and wailord.
There aren't specific Pokemon for battles.You should use your strongest Pokemon.
your strongest Pokemon
FireGrassWaterGhost or DarkElectricRock or Grond
Pikachu's team
You should use either Groudon or your Starter Pokemon. I used a crobat and a garados.
you should use water types because they are strong against fire types
which elite four are you referring to. use bug and fightning move to defeat dark pokemon.
you need all round pokemon with you so you have one super effective for each. they also need to have a high level, as highe or higher than the elite four.
types 2 use: grass, water, fire, electric, psychic, dragon.
Machamp, Alakazam, Gyrados, Articuno, Ninetails, Victreebel.
There is are no certain Pokemon needed to defeat the elite four. Just use your strongest Pokemon.
The types of pokemon the Elite Four use in Pokemon Y are: Steel, Fire, Dragon, and Water. The Champion uses a variety of types.