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After u complete the pokemon leauge..u can go to the Battle tower,by ship .
you cant cause its the end of Pokemon sapphire. but the game Pokemon emerald has the whole battle frontier.
Go to the battle tower
We can get other regions starter Pokemon if we defeat the battle tower
There is no Trainer Tower in Pokemon Pearl. It is only present in Pokemon Leafgreen and Firered and Pokemon Emerald. There is however, a Battle Tower in Pokemon Pearl which is basically the same as the battle towers in Pokemon Ruby, Sapphire, and Emerald.
Pokemon Ruby and Pokemon Sapphire do not have the Battle Frontier, instead they only have the Battle Tower. It was not until Emerald version that the Battle Frontier was added to the game.
Some legendary Pokemon can't enter.
No there isn't. The cave is in Pokémon Emerald
you cannot ever beat the battle tower. but if you have completed the sinnoh pokedex then the battle tower will help you complete it. you can battle at the battle tower as long as you want.
Nothing.
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You Can't Clone On Pokemon Ruby/Sapphire. Only Emerald In The Battle Tower.