You can't. In order to beat the game you must defeat them or there is no way to raise them
a.) you can raise Pokemon the old fashioned way by beating the elite four a lot. b.) clone a Pokemon holding rare candy so you can have loads of rare candies and level up like that.
The Pokemon has to be happy and it has to be night time for it to evolve. You can raise happiness by making your Pokemon holding the Soothe Bell, etc. or by giving it massages at Veilstone City in Pokemon Pearl or the Resort Area (unlocked after completing the Sinnoh Dex and beating the elite four and the elite championship.)
1.get a rayquaza. 2.give rayquaza the exp.share. 3.beat the elite. 4.keep beating the elite 4 until you level up rayquaza to lv.100. trust me ive done it before!
just go crazy catching Pokemon and raise or trade them. or you could restart your game and play it again!!!!or raise your Pokemon more and challenge the elite four againor catch mewtwoor go talk to proff. oak, then celio on one island and start the national dex questgo crazy and lvl up your Pokemon to lvl100 witha party of your six favorite Pokemonwell there are a few things after beating the elite four in leaf green/fire red, normally a guard would be standing in front of Cereleun Cave when you beat the elite four it is possible to get in the cave since the guard is gone, then you can catch MewTwo, it's pretty fun and simple, you can also find legendary dogs running in the grasses of Kanto after beating the Elite Four so it is actually a rare type and after that you can just play the game as it was before.
Catch,raise,battle pokemon. Also, tries to beat the elite four.
Rock/Ground Pokemon from level 55 to 59.
Repeatedly battle the Elite 4 with high level Pokemon with the Pokemon you want to level up holding an exp. share.
There is no Powerfulest Pokemon, But if you raise them to be level 100 they will be really Strong, I have a Serperior Right now at level 98 And it almost beat the elite 4 for me. Also Try Finding Rare Candy's so you can raise your Pokemon to level 100.
NO! Just because you have beaten the elite 4 it doesn't really mean you have completed the game. You can still catch other legendarys and raise your pokemon, get another pokedex to complete and even challenge the elite 4 again if you like.
You don't need to defeat Red twice in a row, although you can keep beating him to raise your stats quickly. When you beat the Elite Four, you can fight Red. Once you've done that, you can't attack him again until you've done the Elite four again. by doing this, you can quickly evolve Pokemon and level up, which is what I've been doing.
Give the Pokemon you are trying to raise its happiness a soothe bell, go battle some trainers or wild Pokemon (i would suggest the elite four) put that Pokemon in the first slot of your party. Then switch him out (if he's weak) and defeat the opponent. DO this for every single opponent( without letting your friendship Pokemon faint).
beat the elite 4 over and over, items like the lucky egg also help your pokes get more exp.