1. Give the pokemon you want to duplicate any items you wish to dupe as well.
2. Save your game.
3. Open your Bill PC, and deposit pokemon/items.
4. Change box, and when the 'saving game' message comes up, turn off your gameboy.
5. Turn your gameboy back on, and you'll still have the pokemon you transferred in your party.
6. Now withdraw your duplicate pokemon and items from your Bill PC! Yeah!
Starting Pokemon (Gold version):
Select one of the following to get your first Pokemon. The names in parentheses are for the Japanese version of the game.
Chickorita (Chicorita): a Grass type, like Bulbasaur.
Tododile (Waninoko): a Water type, like Squirtle.
Cyndaquil (Hinorashi): a Fire type, like Charmander.
In the town with the fourth gym, go inside the second cave and turn to the right and SURF. Go to the top and enter another cave that is there. Make your way around the mazes and talk to the karate character that is there. Defeat him and to will get Buruki. Note: Make sure you have an open space in your Pokemon holder.
If you want a Pokemon rumored to be a pre-evolution of Dratini (Denryuu), do not try to de-evolve Dratini. Instead, go to the route after Kickyou City towards the Connection Cave, and try to capture the electric sheep, Meripu. Let it grow to level 15. It will evolve into a pink sheep. Train it to level 30, and to get Denryuu.
Go to the fourth gym and SURF right all the way. You will SURF in the water should see a Gyarados. Battle it, and it will be golden.
Equip the Metal Coat on Onix and trade it to another GameBoy. It will evolve into Haganal.
Hou-Hou (Gold version):
Go to the city with the fourth gym. Go inside the house with another house beside it. Climb up and enter the other big house. Climb up until you get to Hou-Hou.
Hou-Hou (Silver version):
Go to Pewter City and talk to the old man that walks around. He will give you a gold feather. Now, go to the place where Hou-Hou is located in the Gold version to find it.
Give Gloom a Solar Stone and it will evolve into a Kirehana. You cannot evolve Kirehana into Vileplume.
Enter the cave in the second city and SURF. You should be able to see Lapras. Note: There is only one.
Lugia (Silver version):
Learn HM06 (Whirlpool) and go to the place where you received the fifth badge. Destroy a whirlpoor and enter the cave. Go through the maze and you will reach Lugia.
Lugia (Gold version):
Go to Pewter City and talk to the old man. He will give you a silver feather. Now, go to the place where Lugia is located in the Gold version to find it.
Breed the Golden Gyarados with a regular Gyarados to get a Golden Magikarp.
Breed Jynx with anything that has the same symbol while looking at your party to get Muchuru.
Transfer a Pikachu from Pokemon Yellow into the game. It should have an item directly translated to "Electric Ball". Equip it to any Pikachu, and its special attack will double.
Go to the cave where you go to get to the Elite Five. You should encounter a silver Ryhorn.
Three legendary dogs:
Go to the city with the fourth gym and enter the big house. Break the rocks and fall down one of the holes to wake them up. Then, just go outside and try to find them in the wild.
Defeat the first gym and go into the Pokecenter. Talk to the scientist and he will give you a egg. After 5,000 steps, it will hatch into Togepi.
Equip Symbol Of King on Slowpoke and trade it into another GameBoy. It will evolve into Yadoking.
Breed two Pikachus to get Pichu.
Breed two Electabuzzes and you get Eleckid.
Breed two Clefairies and you get Pi.
Breed two Jigglypuffs and you get Pipurin.
Breed two Magmars and you get Bubi.
Thanks to Revolution readers Danick Fiset, Daniel O'Connell, and Jwyanza!