Pokemon Emerald: Best place to level up to beat the Pokemon League?

definately do not catch rayquaza with master ball it will only waste it, google how you can catch easily without it. the best way to fight the elite four is to challenge the elite four if u beat one of the pokemon youll gain experience and eventually beat 2 and so on and so on eventually ull level up alternative get acro bick put pokemon in daycare and jump by pressing b to ur hearts content(i taped it down and in four hours 30 levels)