There is no Battle Frontier in Ruby. Only in Emerald, Patinum, HeartGold and SoulSilver.
Beat Elite Four.
Beat the Elite four and the Champion.
After you beat the Elite Four, go to the Battle Frontier.
there is no battle frontier in Pokemon pearl,but there is a battle tower. you can go there after you beat the elite 4
yes
Travel to fight area and challenge the BATTLE FRONTIER
you go to a place called the battle frontier where you try beat the battle aces. you also have to fight SSteven who might i warn is very strong. his Pokemon are 20 levels above Wallace. you also have to finish your pokedex.
After you beat the elite you go to the battle frontier and find and catch all the Pokemon in the Hoenn region.
Use a teleporting one or just beat the elite four
You can get to the battle frontier after you beat the Elite Four
You have to beat the elite four, and then receive the s.s. ticket, and take the boat from slateport or lilycove.
You need to beat the Pokemon League or beat Red in the Kanto Region, I forgot so it's one of those two. you have to first beat the elite four and then in olivine city there will be a entrance beside the beach