To duplicate an item make a pokemon hold it and duplicate it.
to duplicate put a pokemon from your party in an empty box in your PC.

Then turn off the gameboy before it finishes saying SAVING DONT TURN OFF THE POWER.

if you have done this right. you should have the pokemon you duplicated pokemon in your party and in the box. good luck =)

After you get on the s.s anne you fight gary and get cut. But after you do that stuff if you faint on the s.s. Anne you can got back after you got surf but don't go on the ship. Surf to the right and you will find a truck. I don't know why it's there but it is and strength can't move it. I can not figure it out. Help me try and post it up here

Use a nintendo event to get Celebi#251 !

For Pokemon Blue, and Red versions only.
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If you're not going to take the time to try it then don't tell me I'm wrong, as I've accomplished this multiple times on multiple games. If you're hesitant about this trick use it on an unwanted game.
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1. First start a new game.
2. Select your Pokemon, and start your journey.
3. Get to Cerulean (Misty's Town).
4. Head up the Nugget Bridge.
5. Now this is important! Do NOT fight the boy with the Slowpoke on the path to Bill's house! Avoid him at all costs! Do NOT fight the man to the left of Nugget Bridge hidden in the grass; in the direction of the Unknown Cave! Avoid him as well!
6. Find and catch an Abra. (Teleport move is needed.)
7. Go to the Cerulean Pokecenter (Very important that this is the last Pokecenter you have visited.).
8. Now go to the top of Nugget Bridge. STOP AT THE TOP! SAVE YOUR GAME!!!
9. Once you've saved head to the left, but DON'T go down! Make sure you're lined up with the man in the grass below. Now walk towards him. The moment you come into view of the man (THE EXACT SECOND!) pause the game.
10. While the game is paused go to your Pokemon, and use Abra's teleport move.
11. If this was done correctly once you teleport the man should get the mark above his head as if he were going to battle you, but you should teleport anyway.
12. To be sure it worked correctly try pausing your game once you arrive at the Pokecenter. If you cannot then it is working.
13. Now go fight the boy with the Slowpoke. Do NOT fight anyone else in between the time you teleport and the time you fight the boy. The only warning is you must walk directly in front of him. You cannot go into his view from a distance. You must go directly in front to the point where he will not have to walk to reach you.
14. Defeat him. Do NOT lose.
15. Start heading back towards Cerulean city. On your way there your start menu will open by itself. Be prepared. Once you close the menu a battle with Mew will start. He is at a very low level, but is none the less still difficult to catch. You should get him to a low amount of life before trying to catch him, as the balls will actually miss.
16. Catch Mew. Its first couple of moves are not very useful. (i.e. Transform, Pound, etc.)
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Wether you believe this or not it's a real glitch in the game. I have proven it, and I'm surprised it's not a more common trick by now. Don't tell me I'm wrong just try it.

In the begining when you turn the GBC/GBA on, hit any of the buttons on the control pad, then press A. You can change the colors! Not really a cheat, but it's cool.

When you place your Pokemon with somebody from the day care, leave the daycare and go to a border between a route and a town/city and keep walking back and forth from the route to the town/city (do this for about 5 minutes) and go back to the daycare and your Pokemon should be much stronger.