Pokemon Heart Gold | Nintendo DS
Catch Hoenn Region Pokémon! / Get EXPN Card
Looking back at the last time I posted this cheat, I was really unclear about some things (probably because I posted it JUST as I found out about it). So, just don't mind the last version.
To get the EXPN Card:
(If you already have the EXPN Card, go down tothe next section)
First, in order to do this, you must have beaten the Elite Four and have gained access to the Kanto Region (I think your mom will give you a ticket for the S.S. Aqua). Now, go to the Power Plant (East of Cerulean City, South of Rock Tunnel) and talk to the manager. He'll be in the upper part of the room in the front. Now, you must go back to the Cerulean Gym and a Team Rocket Grunt will run into you. He's going to run to the Nugget Bridge. Follow him and battle him. Afterwards, head back to the Gym and look near the inner-tubes in the upper left hand corner of the Gym to find the missing piece of the Power Plant. Now, head back to the Power Plant and give the piece to the manager. Now, head over to Lavender Town's Radio Tower and talk to the old guy in the upper part of the room. He will give you the EXPN Card as a thank you gift for fixing the Power Plant and rescuing his job.
Catching Hoenn Pokémon in Kanto:
Now that you have the EXPN Card, you may now listen to more Radio Stations! Let's try this out. Go to the route to the left and find a patch of grass. Now, use your PokéGear and tune in to the station in the upper LEFT hand corner. NOTE: It must be Wednesday for this to work! Now keep doing this until you find some Hoenn Pokémon! Awesome, huh?