It really depends on the type of game that you have. If you have Ruby/Sapphire/Emerald, You must get the Eight Gym Badges of Hoenn. If you have Diamond/Pearl/Platinum, you will receive the Eight Gym Badges of Sinnoh. If you want HeartGold/SoulSilver/Gold/Silver/Crystal, you will get the Eight Gym Badges of Johto AND Kanto. If you have FireRed/LeafGreen/Red/Blue/Green (Japan Only)/Yellow (Pikachu Version), you will ONLY receive the Eight Gym Badges of KANTO.
...you beat the gym leaders
You can get all sixteen badges by defeating all eight Johto gym leaders, defeating the Elite 4, and then beating all eight Kanto gym leaders.
You need all eight badges and you have to have beaten the Elite Four in order to capture Rayquaza.
to get the eight badge go to viridian city after you have 7 badges and enter the gym
we can get 8 gym badges byfighting all the gym leaders in Pokemon pearl.
You have to get all eight badges.
...you beat the gym leaders
Beat the E4 and Champion.
well first of all there are eight badges second you dont find it you have to beat the gym leaders
You can get all sixteen badges by defeating all eight Johto gym leaders, defeating the Elite 4, and then beating all eight Kanto gym leaders.
you have to get all eight gym badges
There are eight badges in kanto though there is a picture floating around of Gary Oak showing that he has ten
You need all eight badges and you have to have beaten the Elite Four in order to capture Rayquaza.
to get the eight badge go to viridian city after you have 7 badges and enter the gym
You have to get all eight gym badges
u get it from blue once you get all eight gym badges in kanto
You need to have all eight gym badges first. I had Pokemon leafgreen but it should be the same. After you get all eight gym badges, you need to go to the city where you face Giovini as the eighth gym leader. you need to go left once you get to the city. it will be called rought two. follow it down, if you have all eight gym badges, you will face your rival on this road. defeat him and then you can advance on. once you get to the building, go inside. you have to go through this winding of people. they will keep asking to see your gym badges. once you have passed the final person, you have to enter a cave. once you get through the cave, it will be right ahead of you. hope this can be of help to any of you people reading this. im sorry for any misakes that i have made in this, i don't have my game right in front of me. thank you