All you need is a Kyogre and a Blaziken to win on the first try. Kyogre needs thunder, surf, ice beam, and you should probably give him Magic Water to kill Metagross and Cradily at low levels. An interesting thing is that thunder never fails for Kyogre if it rains. Simply double kick Absol and Mightyena, thunder on Sharpedo, and ice beam on Shiftry and Cacturne. Then, surf all of Ester's pokemon, as well as Glalie. Use thunder on Sealo and Walrein. Use ice beam on the dragon pokemon, and surf the rest. You can also win with Kyogre alone, but you will need PP Ups or you will have to change things, like thunder on Skarmory and ice beam on Claydol.
Steps
Step 1. It's time to defeat the Elite Four
First of all, it is advisable to get all your pokemon to level 55-60 because the champion will put you in a lot of trouble if you don't.
Step 2. Here is the Elite Four's trainer list for Ruby and Sapphire ~
Step 3. Fosco:
Mightyena, dark, level 46. Shiftry, dark / grass, level 48. Cacturne, dark / grass, level 46. Sharpedo, dark / water, level 48. Absol, dark, level 49.
Step 4. Ester:
Dusclops, specter, level 48. Banette, specter, level 49. Sableye, specter / dark, level 50. Banette, specter, level 49. Dusclops, specter, level 51.
Step 5. Frida:
Glalie, ice, level 50. Sealeo, ice / water, level 50. Sealeo, ice / water, level 52. Glalie, ice, level 52. Walrein, ice / water, level 53.
Step 6. Drake:
Shelgon, dragon, level 52. Altaria, dragon / flight, level 54. Flygon, dragon / earth, level 53. Flygon, dragon / earth, level 53. Salamence, dragon / flight, level 55.
Step 7. Rocco Petri:
Skamory, steel / flight, level 57. Claydol, earth / psych, level 55. Aggron, steel / stone, level 56. Cradily, stone / grass, level 56. Armaldo, stone / insect, level 56. Metagross, steel / psycho, level 58.
Step 8. In Pokemon Emerald, the only difference is the last member of the Elite Four:
Step 9. Adriano:
Wailord, water, level 57. Milotic, water, level 58. Tentacruel, water / poison, level 55. Playful, water / grass, level 56. Gyarados, water / flight, level 56. Whiscash, water / land, level 56.
Step 10. As you can see, there are some hard-to-beat trainers like Drake and Rocco Petri / Adriano
Step 11. To defeat the Elite Four, it is advisable to choose Torchic as the starter
In the latest evolution (Blaziken), learn powerful fighting moves such as Thunderbolt, which will be very useful for defeating Fosco (the dark-type trainer), Frida (the ice-type trainer, but, IMPORTANT, most of her pokemon are also partly water, so be careful) and Rocco Petri (steel type, which is covered by combat and fire moves).
Step 12. Ester is a very complicated trainer because there are excellent ghost pokemon with good Sp attacks
but, unfortunately, ghost moves are physical in this game (poor Gengar). The same goes for the dark types. A good attack but the blind moves are special in this game. So, to defeat Esther, use all your pokemon.
Step 13. For Drake, a quick Salamence will suffice
Aside from the dragon moves that count as specials in this game, Salamence can still win. A water pokemon will also be useful if he can learn Ice Beam (Starmie will be a great choice).
Step 14. Capture Magneton
On the surface it may not seem like a great choice, but you are wrong if you think so. The fantastic special attack and medium speed will make it one of the best electric type pokemon in the game. Use Magneton against Frida and Adriano.
Step 15. Steelix (evolved from Onix) is a good pokemon because you can switch to him easily (except for the fire and water types due to their special attacks)
If you are having difficulty, simply switch to Steelix and use roar on the opponent.
Step 16. As the last pokemon, a grass type
It will resist well against the attacks of Adriano's pokemon and if it is faster, use it to defeat Frida. Sceptile is a recommended choice, but if you can't get it, use Ludicolo.
Step 17. Now, there is a list of recommended pokemon to defeat the Elite Four:
Step 18. Blaziken:
Fire Blast, Stramontante, Granfisico (sometimes you need some defense), Flamethrower (because Fire Blast is sometimes missing)
Step 19. Salamence (level 60 for being faster than Drake's Salamence):
Earthquake, Dragon Claw, Fire Blast, Hydro Pump (if you can get an egg move), or Dragon Dance
Step 20. Starmie:
Ice Beam, Lightning Bolt (excellent combo with Ice Beam), Surf / Hydro Pump (accuracy / power), Catch
Step 21. Magneton:
Lightning Bolt, Cannon Sickle, Locate (great combination with Cannon Sickle), Thunder Wave (to paralyze faster enemies)
Step 22. Steelix:
Earthquake, Steel Tail, Toxin (combines with Steelix's excellent defense), Roar
Step 23. First choice - Sceptile:
Leaf Blade, Dragonclaw (can help you against Drake), Breach, Hyper Beam (as a last resort)
Step 24. Second choice - Playful:
Surf / Hydro Pump (same as Starmie), Rain Dance, Gigabsorption, Parasite Seed (Irritant Healing Set)
Step 25. Choose Swim Swim for Speed and Rain Cover for HP
Good luck defeating the Elite Four!
Advice
- Save before you go to the Elite Four. That way, if you lose, you can just turn off the game, turn it back on and try again or go back to train / change your Pokemon.
- Buy many Tot Refills and Revives. They will be very useful.