Where can I train my Pokemon in HeartGold/SoulSilver after Kanto?

Solution 1:

If you have a Sinnoh game from the 4th generation, the best method is actually to trade them to that game and train them up on the wild pokemon in the Battle Zone (the island containing the battle frontier), especially Route 227 and Stark Mountain.

The highest level wild Pokemon in the Johto remakes are the level 45-50 Pokemon in Mt. Silver and the lowest floor or Cerulean Cave.

If you don't have any Sinnoh games, your best option is to keep doing rematches with trainers, which can be found by the exclamation marks next to route names on your Pokegear map (some of those trainers just want to give you items, but most are rematches). or just keep attempting the Elite Four, even if you don't succeed (though this may drastically lower your Pokemon's happiness because of the repeated fainting).

Another option is to do Gym Leader rematches in the Fighting Dojo in Saffron City, but this is slow because you can only fight certain Gym Leaders each day, and you need to collect their phone numbers beforehand. A guide to getting the Gym Leader's phone numbers is available on Bulbapedia.After you get their phone number, call them at the correct time, and they will show up in the Fighting Dojo.

Their Pokemon are levelled up significantly. Most of the Gym leaders are in the 50-60 range, but some (Blue) go up to level 70.

Solution 2:

One option is to battle wild Pokemon in Mt. Silver. You'll encounter Pokemon from levels 40 - 50 there.

Another option is re-battling Gym Leaders. Serebii has a page detailing how to obtain their phone numbers, and what Pokemon they have. I find this the most efficient way because during the timeframe that you can rematch them, you can battle them as many times as you want. Call them, battle them, leave the dojo, and repeat. As you are battling a trainer, you get 1.5x the experience you would obtain from battling a wild Pokemon of the same species + level.

If you don't care about your Pokemon's happiness, and have a Sinnoh game, you can trade them over and fight wild Pokemon there (I would suggest Stark Mountain). Trading over a Pokemon to another game will reset it's happiness, but they will gain 1.5x the experience they would in their native game.

Solution 3:

The thing I do is trade over a level 100 from a previous game to the new game, get an exp share and put it on the the Pokemon (or Pokemons) you want to level up. Go through the elite four or just battle randomly. That should level up your Pokemon well!

Solution 4:

Well, I have many tips:

• Use rare candies (search up where to find all of them
• Go to mount silver and you get around 1000 exp per win on the wild pokemon
• Battle the gym leaders again by getting their phone numbers and calling them on the right time
• Battle the elite 4 again
• Go to the day care centre and put pokemon in and go to the gym in ecruteak city and put something heavy on the 'up' button and leave your ds in charge overnight (I preferably tape down the button)
• Battle red at the top of mount silver
• Have a traded pokemon (this allows it to gain more exp from battle)
• Catch several chanseys from the safari zone or the mary and oak swarm and they have a 5% chance of holding an item called lucky egg that gives you 50% more exp from battle
• Teach it powerful moves so it is more powerful therefore wins more battles
• Give it drinks (e.g. carbos) to increase stats therefore winning more battles get a high level pokemon in ypur party and the one you want to train at the front and start a battle and switch to the high level pokemon straight away and win

Using these methods, I got my houndour level 15 to a houndoom level 100 in less than a week.

Hope I helped. Good luck!