train like heck
You have to love and train your Pokemon.
you could use action replay but if you dont have action replay train at the Pokemon league which will take about a day depending on its level when you start.
Train your Pokemon to level 100 or just keep it in the daycare for an extremely long time.
You can't there are only three ways to get a lv100 train, trade, and migrate.
yeah but you have to beat the elite four 20 times and get national pokedex his Pokemon are 1: torterra LV100 2: empoleon LV100 and 3: infernape LV100 trust me i have defeated the elite four 28 times It actually good to do that cuz you train your Pokemon a lot
the Pokemon league and maybe cerulean cave
Mt. Silver or the Pokemon league
train them en beat gyms for the league
At the Pokemon league.
You could train in Victory Road. It has the highest leveled pokemon. Thanks very much.
Train them by defeating the Pokémon League over and over again.
You can train the Pokemon until they reach level 100 (Which will take a long time) or you can hack the game for unlimited rare candies. Although using that method, the Pokemon's stats will be lower then if you leveled them up the legit way.