99 of Any Item
To get 99 of any item, first put the item you want to multiply in the 6th spot. 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" (a glitch like Missingno) Once you see him, kill him or run away. DO NOT CATCH HIM! After that, you should have 99 of your 6th item!
Celadon City Slot Tip
All of the slot machines have different odds, which change every time. Play each machine 4 times, and if it hits 2 or more, then stick with that one, because it's probably hot.
If the slow machine forces you really close to a 777 or Bar Bar Bar it will probably give you one or the other soon.
Cut Down Grassy Areas
Once you get the HM "cut", your pokemon can cut down grassy areas. Use "cut" and it will cut a two by two area. Wild Pokemon will not attack you in the area you cut.
Defeating Sabrina
When you enter the Saffron City gym you'll see a warp next to a trainer. Step into it. You'll appear in another room full of warps and a Trainer. Step into the warp on your left. Then step into the warp below you. Then step into the warp on your left. And then, step into the warp on your left.
Once you've done that you'll come in to a room with one warp and that's the one your standing on. Now talk to the trainer in the room, and get ready to defeat Sabrina.
Here are the Pokémon she will use:
These are all phsycic Pokémon and very powerful. Your best bet against these guys is a Venusaur or other grass-type Pokémon. Use your Razor Leaf if you have a Venusaur.
Easy Celadon City Slot Machines
To make the slot machines MUCH easier simply hold select while playing a machine.
Easy Level Gain
To easily gain experience, simply switch the Pokémon you want to train with the top Pokémon on your list. When you go into battle the Pokémon will pop out. You can then switch to another Pokémon. Once you win the battle the beginning Pokémon and the fighting Pokémon will both gain experience points.
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 Mewtwo
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.
Get MissingNo
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.
Secret Coins
At the Game Corner there are secret coins lying around. You can get these coins by walking around and pressing the A button.
Stone and Trade Evolution
Some Pokémon will only Evolve when they have been traded. They are:
Before = After
Machoke = Machamp
Graveler = Golem
Haunter = Gengar
Kadabra = Alakazam
Some Pokémon don't Evolve till you give them a Stone. They are:
FS = Fire Stone
TS = Thunder Stone
WS = Water Stone
LS = Leaf Stone
MS = Moon Stone
Hint: You can get the stones in the Mart in Celadon City.
Before = After
Pikachu + TS = Raichu
Nidorina + MS = Nidoqueen
Nidorino + MS = Nidoking
Clefairy + MS = Clefable
Vulpix + FS = Ninetales
Jigglypuff + MS = Wigglytuff
Gloom + LS = Vileplume
Growlithe + FS = Arcanine
Poliwhirl + WS = Poliwarth
Weepinbell + LS = Victreebel
Shellder + WS = Cloyster
Exeggcute + LF = Exegguter
Staryu + WS = Starmie
Eevee + WS = Vapereon
Eevee + TS = Jolteon
Eevee + FS = Flareon
Truck Glitch
When you get to Fuschia City, don't go on the S.S.Anne and get cut. Get the HM03 which is in Surf. Go back to the S.S.Anne and while you are on the bridge to the ship, surf off to the right. You'll end up on a strip of land and you will see something that looks like a truck (Mew is not on that island).
Use a Pokéball as a Masterball
Throw a regular Pokéball then hold DOWN + B until the Pokéball explodes.
Pokemon Duplicate Code
First, have 6 Pokemons. Among of them, one is that you want to copied (you can't copy one with a HM or TM ability), and the one that is to be overwritten. Place the Pokemon to be copied at the bottom. Put 5 Pokemon in your PC without the Pokemon to be multiplized. Take 4 Pokemon of the five from your PC. Make sure that you have the one to be overwritten. Place Pokemon to be overwritten at the bottom spot and the Pokemon to be copied at the top. Push the start button and go to the items menu. Push select on the 6th item. Then push the B button twice. Go into a wild Pokemon battle. When it starts, send out the 6th Pokemon (to be overwritten). It will then disappear from display. Push the B button and select run away. Go to the Pokemon Daycare. The daycare guy will ask you if you want a pokemon back. Take the pokemon he offers back. It is the same pokemon you got is the same as the 1st Pokemon.
Pokemon Gameshark Codes
These codes, start with 01XX1ED1. The two X'S are for the codes underneath:
Bulbasaur-99 Ivysaur-09 Venusaur-9a Charmander-b0 Charmeleon-b2 Charizard-b4 Squirtle-b1 Wartortle-b3 Blastoise-1c Caterpie-7b Metapod-7c Butterfree-7d Weedle-70 Kakuna-71 Beedrill-72 Pidgey-24 Pidgeotto-96 Pidgeot-97 Rattata-a5 Raticate-a6 Spearow-05 Fearow-23 Ekans-6c Arbok-2d Pikachu-54 Raichu-55 Sandshrew-60 Sandslash-61 Nidoran(female)-0f Nidorina-a8 NidoQueen-10 Nidoran(male)-03 Nidorino-a7 NidoKing-07 Clefairy-04 Clefable-8e Vulpix-52 Ninetales-53 Jigglypuff-64 Wigglytuff-65 Zubat-6b Golbat-82 Oddish-b9 Gloom-ba Vileplume-bb Paras-6d Parasect-2e Venonat-41 Venamoth--77 Diglett-3b Dugtrio-76 Meowth-4d Persian-90 Psyduck-2f Golduck-80 Mankey-39 Primeape-75 Growlithe-21 Arcanine-14 Poliwag-47 Poliwhirl-6e Poliwrath-6f abra-94 Kadabra-26 Alakazam-95 Machop-6a Machoke-29 Machamp-7e Bellsprout-bc Weepinbell-bd Victreebell-be Tentacool-18 Tentacruel-9b Geodude-a9 Graveler-27 Golem--31 Ponyta-a3 Rapidash-a4 Slowpoke-25 Slowbro-08 Magnemite-ad Magneton-36 Farfetch'd-40 Doduo-84 Dodrio-74 Seel--3a Dewgong-78 Grimer-0d Muk-88 Shellder-17 Cloyster-8b Gastly-19 Haunter-93 Gengar-0e Onix-22 Drowzee-30 Hypno-81 Krabby-4e Kingler-8a Voltorb-06 Electrode--8d Exeggcute-0c Exeggutor-0a Cubone-11 Marowak-91 Hitmonlee-2b Hitmonchan-2c Lick0itung-0b Koffing-37 Weezing-8f Rhyhorn-12 Rhydon-01 Chansey-28 Tangela-1e Kangaskhan-02 Horsea-5c Seadra-5d Goldeen-9d Seaking-9e Staru-1b Starmie-98 Mr. Mime-2a Scyther-1a Jynx-48 Electabuzz-35 Magmar-33 Pinsir-1d Tauros-3c Majikarp-85 Gyarados-16 Lapras-13 Ditto-4c Eevee-66 Vaporeon-69 Jolteon-68 Flareon-67 Porygon-aa Omanyte-62 Omastar-63 Kabuto-5a Kabutops-5b -Aerodactyl-ab Snorlax-84 Articuno-4a Zapdos-4b Motres-49 Dratini-58 Dragonair-59 Dragonite-42 Mewtwo-83 Mew-15
To catch Mew
0115D8CF, enter this code. Next, go to any grass and walk around till u meet a pokemon, which is a mess-up pokemon[Mew]. Capture it before it uses the ability transform and after u take it out from your computer, Mew will not be a mess-up picture.