if you mean what Pokemon are easy to train, the easiest Pokemon to level up and stuff is your starter Pokemon. it's the same with Ruby and Sapphire, the start Pokemon always seems to level up quicker than caught Pokemon (at the beginning anyway) hope that helped :3 *Shi ~
level him up to level 35
I can't level up your rayquaza but I can level up mine.
Elite 4
try rare candies
YOU LEVEL IT UP PATIENTLY!!!!!!!!!!!!!!
no point hacking u no...
Get a corphish and level it up to level 20 or so and it will become crawdaunt.
You catch a Slakoth in Petalburg Woods then level it up to level 18.
Easy play well
shut up it easy buy in mauville shop
Repeatedly battle the Elite 4 with high level Pokemon with the Pokemon you want to level up holding an exp. share.