Here is a code to get dollars. Go to the Rocket Game Corner in Celadon City and keep buying coins from the guy that gives you those starting coins. Keep buying and buying abd buying until you have 6,500 coins (or how manymake a pokeball catch a pokemon 100% of the time (even when it isn't a Master Ball) When you see the ball being thrown, press up and B. The pokemon should be caught. It isn't an easy trick, but once you get used to it, it really works!
Here is a code to get 199 of any item Fly to Viridian City. Move the item you want 199 of to the 6th spot on your list. Talk to the old man and watch him catch a weedle. Then, fly to Fuschia City and and surf to the coast of Seafoam Island. DO NOT GET OFF!! Surf until you find a pokemon that looks like a Missingno. Either run away or defeat it, just do not capture it!! Afterwards, check on your item list how many of that item you have. There will be 199.
Here is a trick to get Mew (new) Buy the Magicarp from the guy at the pokecenter in Mt. Moon. Bring the Magicarp to the pokecenter and leave it there until it is at level 50. The Magicarp is supposed to evolve into Mew. I really don't see how that works, but try it anyway!!
Here is a code to get a Pokegod (new) Beat the Elite Four 30 times and don't talk to the nurse or anyone at Indigo Plateau(or anywhere else for that matter). After you beat the Elite Four the 30th time, Professer Oak will say, "I'm getting tired of this." He'll let you walk around the Hall of Fame which leads to a new city where people swap Pokegods. What exactly IS a Pokegod? Try this code and find out!
Here is a trick to get any pokemon to level 100 (new) Use the code to capture 199 of any item and get 199 rare candies. Keep giving your pokemon rare candies until it is at level 100. Simple as that!
Here is a code to get all 150 pokemon Trade with a friend, and while your pokemon are trading, keep pressing A. You will get all 150 pokemon. But I don't know what happens to your friend....
Here is a code to catch Missingno First you need the fly and surf techniques. Now, fly to Viridian City. Talk to the old man and watch him catch a weedle. After that fly to Fuschia City and Surf until you reach the coast of Seafoam Island. Surf along that area and you will run into a pokemon called 'M. Its attack is really strong but its defense is really weak. Use a weak pokemon on him. If you keep surfing along the Island, you'll run into level 128 Haunters! WARNING: Catching him may cause some minor glitches. If you don't like them you can release him and the problem should be fixed.
Here is a code to capture Porygon(new) Use the Item Duplication Code and get 199 nuggets. Then, sell all your nuggets and and get 999,999 coins Porygon is worth). Now, go trade your coins for Porygon at the Coin Trading Center and-voila!-you have Porygon.
Get a blue pikachu: ( Not proven to work...yet) Okay, so you've gotten all the pokemon, you must go to Ash's house and talk to the mom several times. Than she will stop treating your pokemon and say "Your pokemon are well! By the way I found a blue pikachu!" Then she will give it to you. Do not e-mail me for this cheat.
Nido God's soul: To do this you must kill Ash's mom. Talk to the person who shows you how to catch a weedle 1000 times. Then go to back home and you will find ash's mom dead. Talk to the soul and the soul will fly to you Nido Kings body and he will evolve into Nido God!
Pokedex or Pokemon:
This code is very tricky, talk to the Saffron city gaurd 1000 times. At the 1001 time he will say "I am going to give you 300 pokemon, by the way you mother's dead." Ash will return to his home and find a ghost there. You are suppose to fight and catch it, after she will give you the choice of having a pokemon gods pokedex, or pokemon gods.
Duplicating pokemon: To duplicaate pokemon you will need 2 gameboys and a link. One needs to get a bad pokemon and the other the one that has the pokemon being duplicated. When you trade, the one who has the pokemon being duplicated has to turn it off when it says plase wait. I wouldn't recomenned doing it a lot because it might erase your game.
Duplicating Items: To duplicate items, you must put hte item you want to duplicate on the 6 spot. Talk to the guy in Viradian City who catches the weedle and then go to the coast of Cinnabar Isalnd. Surf up and down until you find a M. Kill it and your item will be duplicated.
Pokemon Factory: This is just a rumor but maybe you can be the first to do it. Fight the elite 4 30 times without talking to anyone except Nurse Joy. At the 30 time, Professor Oakwill say, " I am getting tired of this, just look around, than look around. You will end in another city where people will ask to trade normal pokemon for poke gods. Try it!
How to catch a togepi: To catch a togepi you will need an item finder, go to mount moon and use the item finder 100 times, at the 101 time it will beep, look for the egg and you will have a togepi. Play long enough and it will hatch!