you can't! i believe that if you cheat a go through walls cheat, you'll end up freezing and freaking crash your game ;(!
... U can't use the vs sneeker in the underground...
use the VS. Seeker
Heart Gold, Duh new answer: i think platinum is better cause you can get the chance of getting more legendaries than heartgold (heartgold can only get ho-oh and lugia as well as 4-2 extra legends) i have Pokemon platinum and i have gotten 9-10 legendaries + without getting or using the action replay
Onix and weedle
Kerris Dorsey.
Vs seeker
yes
no you can't
You may need to find the vs. seeker in Pokemon Diamond, Pearl and Platinum. You can get this item on route 207.
Give her a giant purple ditto
There are various good places to train flying types in Pokemon Platinum. A good thing to do would be to use the vs seeker.
For FireRed and LeafGreen, you receive it from a girl in the Vermillion City Pokemon Center. For Diamond/Pearl/Platinum, you receive it after you get your bike and go down Cycling Road. You will meet Dawn/Lucas, and they will give you both the VS Seeker and the Dousing Machine.
yes, you can use the VS seeker to get infinite money and exp, just keep using the vs seeker and battling people for infinite money and exp too!
no they can not come back the best way for you to get thm is to save before vs them
you can use the vs seeker and battle to get more experience points or you can go to Pokemon center and battle the reporters
In vermilion city, go to the Pokemon center and talk to the girl next to the counter she gives you The vs seeker.
Go into the vermillion city Pokemon center and talk to the girl near the nurse that heals your Pokemon she will give you the vs seeker.