field sanitation team
You defeat them by training against wild Pokemon.
If you defeat the elite four and lance then you go to the Kanto reigon to defeat the other eight gym leaders the you will fight the boss after you have the 16 gym leaders.
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18
Defeat all 16 Gym Leaders in both Kanto and Johto. If you want a more detailed explanation of how to defeat the gym leaders, go to Seribii.net.
Defeat all 8 gym leaders, then defeat the elite 4.
defeat the mossdeep city gym leaders and you will receive it after their defeat.
after you defeat 4 gym leaders. 8-)
You have to defeat all of the gym leaders.
you must have higher level Pokemon to defeat gym leaders with only three Pokemon you need pikachew,scwirtle and ckiarita
you must defeat 7 gym leaders
Defeat all Gym Leaders ..lol