The Elite Four's first opponent you will have to face is Sydney.Sydney has his team full of dark type pokemon.So that means that you will want to use fighting type attacks against him, But if Sydney brings out his Shiftry or his Absol they will completely destroy your fighting type pokemon with their Extrasensory move and Aerial ace move.So you should switch your pokemon out for another pokemon that isn't weak to Sydney's Absol, And Shiftry's attacks.When Sydney's grass and bug type pokemon start to battle the you will want to usebug type strikes to deal extra damageto his pokemon, because they will get a double damage multiplier.But make sure not to use any psychic type pokemon because Sydney's elite team will knock then out fast with his pokemon's dark type moves.
Next in line in The Elite Four is Phoebe.Phoebe has a strong team of all ghost type pokemon except for her Sableye which is ghost and dark.Only two types of attacks will harm these pokemon.Ghost is a good type of attack to use, but make sure not to use them with a ghost pokemon because Phoebe's pokemon's moves will be highly effective to your ghost pokemon.You will be better off though by using dark type attacks being delivered by dark type pokemon for maximum efficiency.Don't even bother trying to use fighting or normal type attacks against Phoebe's team.They're useless aginst ghost type pokemon.If you wanna play it safe and go on the defensive then bring ou steel type pokemon for a good defense.
Thr third person in The Elite Four is Glacia.Most of her pokemon are ice and water type pokemon, but some of them are just pure ice pokemon.No attack from any pokemon will deal dual damage to the outstanding ice and water type combo.Use your best fighting or electric type moves.Also think about giving Glacia's pokemon some status conditions to make it a little easier on yourself.Then if you inflict one of Glacia's pokemon with sleep or paralyze then every turn yu will be able to attack freely without getting a return hit from one of Glacia's pokemon.That is an easy way to get down their HP.Another good thing to have is a pokemon with the "Thick Fat" ability you will have extra protection against her pokemon.
The last person in The Elite Four is Drake.Drake has dragon type pokemon, but most are dual types with dragon.Drake's Kingdra can't be taken out with an ice type move so use other very powerful attacks.Most of Drake's pokemon will have amazingly strong attacks such as "DragonBreath" and "Dragon Rage".An easy way is to just use dragon type attacks against his dragon type pokemon.Just make sure the dragon type attacks are delivered with pokemon other than the dragon type.Ice attacks are a good way to kill his dragon pokemon,and especially to take Drake's Flygon down to the ground.But make sure when you are using those ice type attacks that they are not being delivered from a ice type pokemon because of the four pokemon in Drake's arsenal that have moves that will oblitterate any ice type pokemon.(Glalie Walrein Sealeo)
The champion of The Elite Four Is Wallace.Wallace has an incrediible team of water type pokemon and raised them all to ver high, deadly levels.Confront him with either electric type pokeone or grass type pokemon.Attack his Ludicolo with poison type and flying type attacks.Wallace's Tentacruel and Milotic have high special defenses so watch out, and use items from your inventory to bulk up.To knockout his Whiscash you must not try to use electric type moves, but instead you can deal massive damage with a grass type attack.