In order to gain lots of experience at once, you must focus on raising one pokemon at a time, (No Exp. Share) and battling against Pokemon of a higher level. There is no easy way to do this other than finding a high-level Pokemon (At least at Level or above) with plenty of weaknesses and repeatedly battling them.Trainer battles result in much more Experience than wild pokemon, and rarer pokemon give more experience than common ones.
you evolve a duskull at lvl 37 one of the best ghost Pokemon on emerald
at level 20
I've looked on the internet and so far the easiest Pokemon to train is Happiny, Chansey and Blissey, I'm not sure if you can find them on ruby, sapphire or emerald, but they only require 800,000 exp to lvl 100!!! Bug Pokemon. -Vicky is Sicky.
You should get a Duskull and evolve it [it evolves at lvl 37 to Dusklops] then get a Shuppet the evolve that [it evolves at lvl 37 too] then teach it a ghost type move or dark type move, then train and that is how to beat the 7th gym leader in Pokemon Emerald. Good luck!!
You get Gardevoir by evolving Ralts to first Kirlia at lvl 20 and it will evolve to Gardevoir at lvl 30
u train at mauvile city (re-battle the trainers)
train it to lvl 38 and trade it then pickaboo it will evolve into kingdra
Try the grass in Lilycove City, or go train in Victory Road.
Give your Pokemon a Rare Candy,or give it an Exp. Share and train.
It evolves at lvl 45.
You level a Pokemon up.
Go to the Pokemon league and train. By Kha111
That's a great party, just train them to about lvl 60 and your ready to kick butt.
how to beat Pokemon emerald
you evolve a duskull at lvl 37 one of the best ghost Pokemon on emerald
Get it to lvl 40
levels 60-75 will do It would work but if you want to win fast get a lvl 50-60 swampert and catch rayquazza and if you want catch a dragon type which knows some good moves to take down most Pokemon