This game is more popular (was) than any other game.
This game featured you as a ten year old who just got a Pocket Monster from a kind Professor, Professor Oak. Professor Oak had a grandson, Gary. He poses as your rival in the race to be the World's best Pokemon Trainer!
Your object is to capture as many Pokemon as you can find, train them, and triumph as the best over the other Pokemon Masters of the world.
Note: This trick requires another Game Boy, link cable and Pokemon game.
Trade the Pokemon to be cloned, and have the other player select a Pokemon that he or she does not care about. Trade them, and make sure the player receiving the bad Pokemon can see the other player's screen. When the Game Boy that receives the good Pokemon's displays "Waiting", get ready to shut the other Game Boy off. When the "Waiting" message disappears, turn off the Game Boy that is receiving the bad Pokemon. When the "Trade completed" message appears, turn off the remaining Game Boy. Both games will have the same good Pokemon when they are turned back on.
Note: Do not attempt this trick with any saved games you wish to keep, as it can corrupt those files if done incorrectly.
To get 99 of any item, first put the item you want to multiply in the sixth item slot. Now use FLY and go to Viridian City. Talk to the old man almost all the way north of the town. When he asks if you are in a hurry, say no and watch him catch a weedle.
Right after that, fly to Fuchsia city. Make your way south and, when you you reach the water's edge, use SURF and make your way to Seafoam island.
When you get to seafoam island, swim up and down the beach until you run into a Pokemon called "M" (Missingno.) Once you see him, kill him or run away. DO NOT CATCH HIM! After that, you should have multiple copies of your sixth item!
Fight Land Creatures in Water
To fight creatures that normally live on land in water, go to the water around Cinnabar Island or Seafoam Islands (The only place you can be randomly attacked while swimming.) Swim along the shore of any island and you will fight land creatures. (You have to swim on a place where the square is half land and half water.)
Instead of fighting a set group of monsters in the water, you actually fight monsters from the last place you were. So to get safari zone monsters, you need to go to the section of the safari zone with that monster, let your time run out, then go to the coast. Using this trick I have caught Kangaskhan, Scyther, and Tauros!
Get Amnesia Psyduck
Have you ever wondered how you can get the elusive Amnesia technique? Well, it's hidden deep in Pokemon Stadium for the Nintendo 64. Unlocking it will take a while, but it's definitely worth it. You have to register ALL 151 Pokemon in the Hall of Fame. Whenever you beat a tournament (or Gym Leader Castle), your six Pokemon are entered into the Hall of Fame. It doesn't matter whether you use rental Pokemon or your own, but you can't have any gaps. Once you've filled it all up, you are awarded a free Psyduck bonus Pokemon that knows the Amnesia technique. You can now upload it to your Game Boy pak and use it in your quest.
After you have gotten all eight of your badges you need to go beat the pokemon league. The credits will roll and then the menu pops up again. DO NOT RESET THE GAME!!!! Go to Cerulean Citygo north to the brige where you faced 5 trainers before the path to Bill's house. Turn left and there will be a large area of water. Surf until you get to a cave. You will find Mewtwo in that cave.
Warning! Catch missingno in the red version may delete your old game and prevent you from saving any other games.
To get MissingNo (a glitch) go to Cinnabar Island and go into the Pokémon Research Labratory and trade with anyone in the first room. Then leave the Lab and go to the EAST of Cinnabar Island and surf up and down on the part where the land meets the water. Eventually the battle screen will come up and the screen goes black for about 5 seconds.
Once you find him I suggest you use a Level 30 to 40 Pokemon. This is because Missing No., even at Lv. 80, has a VERY low defense rating. So get him down pretty low. Even at low he is still extremely difficult to catch. So next get a Pokemon that knows a sleep move and put him to sleep. Follow this up with a couple Ultra Balls and you should have him.
NOTE: Catching MissingNo. may cause minor glitches. Also note that if he evolves (i.e., by receiving a Rare Candy) he will turn into a Khangiskahn.
Get Surfing Pikachu
Did you know that you can get a Pikachu that knows the Water technique Surf? Here's how you can get it (outside of winning a Nintendo Pokemon contest):
Surfing Pikachu is hidden in Pokémon Stadium for the Nintendo 64. To teach your Pikachu Surf (a technique it can normally not learn), you need to first unlock the R-2 (Round 2) mode. Then do the following:
Enter the R-2 Prime Cup's Master Ball division (you have to beat the first three divisions first).
Assemble a team that contains a Pikachu that does not yet know Surf. You HAVE to use a Pikachu from your Game Boy game. You cannot unlock Surfing Pikachu using a Rental Pokémon.
Do not register your team! Pick it directly from your Game Boy cartridge.
You now have to beat the Prime Cup's Master Ball division using a three-Pokémon team that always contains Pikachu. Pikachu has to be in every one of the eight battles.
You are not allowed to use any continues. If you do, you won't get Surfing Pikachu.
Once you have fulfilled all the above conditions, you are shown an award screen with Pikachu standing on a surfboard. From here on, Pikachu can use the Surf technique both in battle and during gameplay (Game Boy versions only). In Pokémon Yellow, you can now also access the hidden Surfing Pikachu mini-game on Route 19.
There is also a GameShark code that lets you access Surfing Pikachu, but we advise against using it, since it can mess up your Pokédex and save data. It's not worth the trouble.
submitted by Peer
Get the Mimic TM
Buy a Pokedoll in Celadon Mart, then FLY to Saffron and talk to the Copycat. She will give you the Mimic TM.
Level 100+ Pokemon
Follow these instructions to catch pokemon with really high levels.
Talk to the old man in Viridian City who shows you how to catch pokemon.
Fly directly to Cinnabar Island.
Put your strongest pokemon on your team.
You might want to save now.
Surf on the shore where the land touches water.
Keep Surfing until you run into one of these strong pokemon.
These pokemon are well above level 100. Unfortunately, they will revert back to Level 100 if they gain any experience points. Rare Candy is the only thing that raises their level. They can be used in a two-player battle without losing their level, so have fun liquidating your friends!
NOTE: This is a bug in the game. It will not work in newer versions of Pokemon and may crash your game if you try it.
Only Way to Get Mew
We've seen so many fake Mew codes pop up on the web (and we get about 20 new fake Mew code submissions A DAY) that we've decided to add this following disclaimer to our codes section:
According to Nintendo, Mew cannot be found or caught in Pokemon Yellow, Red, or Blue. Outside of a GameShark code (which may mess up your Pokedex and render the game incompatible with Pokemon Stadium), the #151st Pokemon remains a cool litte extra that is only handed out by Nintendo on special occasions, such as Mall Tours or Pokemon events.
However, all those who want to catch a glimpse of the rare Pokemon can select Mew as a rental Pokemon in Pokemon Stadium for Nintendo 64 (but you cannot upload it to your Game Boy game). Note that Mew is just that -- a bonus Pokemon (albeit a very cool one that can learn all TMs) -- and not technically required to complete your Pokedex.
At the Game Corner there are secret coins lying around. You can get these coins by walking around and pressing the A button.
Alternate Pokemon Colors
Did you know that there are Pokemon hidden in Gold/Silver that have alternate colors, aka shiny status? There is no easy way to find them (except for the Red Gyarados in the Lake of Rage) as they appear at random -- but they're out there. If you see specially colored Pokemon, be sure to catch them as they are very rare. You can recognize them by the sparkle effect when they appear in battle, or by checking on the Pokemon Status Screen. Next to the Male/Female symbol, these special Pokemon are marked with three dots.
There are any number of these rare types, including alternate versions of Nidoking (dark blue), Golbat (purple/green), Tentacruel (green eyes), Rapidash (purple), Scyther (orange/green), Hoothoot (yellow/purple), Sudowoodu (green/red), Ho-oh (yellow/orange), and more.
At the Daycare Center south of Goldenrod City on Route 33, you can give a male Pokemon and a female Pokemon to the keepers to breed new Pokemon.
Breed two Pikachus to get Pichu.
Breed two Electabuzzes and you get Elekid.
Breed two Clefairies and you get Cleffa.
Breed two Jigglypuffs and you get Igglybuff.
Breed two Magmars and you get Magby.
Breed a Venonat with a Pinsir to get Pinsir.
Breed a Hitmonchan or Hitmonlee with a Ditto to get Tyrogue.
Breed a Clefairy with a Snubbull to get another Snubbul.
Breed a Gyarados with the Red Gyarados to get a golden Magikarp.
Replace any of the Pokemon with the genderless Ditto if you've only got one of a kind. Ditto will act as a wildcard Pokemon.
For more on Breeding, check out the Breeding Section in our Strategy Guide.
Duplicate Items/Clone Pokemon
Note: Use this code at your own risk. It may corrupt your save data if done incorrectly.
Go to a PC, and save. Attach the item you want to duplicate to the Pokemon you want to clone. Deposit it into the PC. Change boxes. When the screen is saying "Saving the game..." Turn off your GB. Turn it back on. You should have the deposited Pokemon in the PC, and a clone of it in your lineup. The item will either be on both monsters, or in your Backpack. Note: while doing this code, DO NOT withdraw any Pokemon. When the GB is turned back on, you'll find that the withdrawn Pokemon has been deleted. Note: You can duplicate up to 5 items/Pokemon at a time.
While the credits are being displayed you can hold the B button to make them go faster.
(A strategy guide will come soon)