This code should work, even though I typed it from memory (I memorized it some time ago). If I typed it wrong, then check Riolu Aura Sphere Now's HG/SS Action Replay codes on Project Pokémon.
Anyways, here's the code:
Press SELECT to obtain National Pokedex (only use if you are unable to obtain it normally)
94000130 FFFB0000
B2111880 00000000
200015FF 00000001
D2000000 00000000
INSTRUCTIONS:
1) Start up the game with the code enabled.
2) Press the SELECT button.
3) (optional) Check to see if the code worked by opening your Pokedex. If not, check out Riolu Aura Sphere Now's AR code thread on Project Pokemon forums and look for "Obtain National Pokedex."
4) Save the game, then re-boot the game with the code turned OFF.
5) Enjoy your quest to complete the Pokedex!
I was so happy to find that the code actually worked, because I used the Walk Through Walls code to go battle Red early in the game and catch his Pikachu. I didn't realize the consequences of doing this, but like I said, I was so happy to find the code.
Shellos
In the National Park.
You can find sunkern in national park
Mew.
You can obtain Togepi from a man, after you defeat Falkner, go to the pokemart and a man gives in to you.
mystery gift
No
Shellos
Listen to the radio on the Pokégear on Wednesdays after you obtain the National Dex. Go to the place where the desired Pokémon appears and play the music.
In the National Park.
it is a item that you obtain in pokemon soul silver that you use to catch lugia the legendary bird in the whirl islands.
to trade Pokemon from different generations in Pokemon games both games must obtain the national dex hope it helps:)
You can find sunkern in national park
i am sorry but you cannot obtain arceus in Pokemon heartgold or soulsilver.
West of the National Park.
Steelix, after National Dex Wailord
Mew.