Mewtwo or zapdos are best for the first guy but they will kill zapdos quick if he doesnt attack first. Articuno and mewto for the 2nd guy.i have a charizard and he wipes the 3rd person out quick. And charizard and mewtwo for the last 2. Then have 2 Pokemon to help if any thing goes wrong. So i have suicune and moltres for back up
You need to get the Pokemon that are super effective against the Elite Four and Gary, (your rival) the champion
get all the super effective types including for last one and defeat everyone and save
Ghost or dark type moves are super effective against Physic.
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.
Any Pokemon that is super effective against the elite 4 and I chose a water and steel, grass and ground,dark and ghost, fire and fighting, flying and normal and a psychic type .
There is not a strategy to beat them,so the only advice i can give you is try to get all of your Pokemon to level 52,or try super effective hits,The elite four has a psychc,ghost,ground,and fighting type trainer. I really hope you beat the elite four trainer. actually, it is psychic,ghost,dark,fighting
get strong EFFECTIVE Pokemon
It really depends on the Pokemon that you have. Use level 100 Pokemon if you have any (if not, use strong Pokemon). Also, use super-effective moves.
if your pokemon is level 45 and over and you would like to train it go to the elite four and get to the guy or girl your pokemon is super effective on then battle it .
The elite fours Pokemon are all lvl 50ish so have a good team at about lvl55+ and you should be okay I recommend taking a dark Pokemon because it will be super effective against two of them the elite four are types are, ghost phychic dark and fighting you can fight them in any order you want
Mewtwo is good for beating the elite four (2nd turn), since it can learn moves like Flamethrower, Thunderbolt, Ghost Ball, Phsycic. All these moves are good since they're all special attacks and Mewtwo is one of the best Pokemon in sp.atk. These moves are also super effective versus almost everyone in the elite four and this enables you to beat the elite four fairly easy the 2nd time.
fishing at the waterfall just before the elite four with the super rod