I found some "farfetched" stories to find Mew in the game. some of them say there's a truck you find mew in with a key you get from "battling" Professer Oak!
Here are the quotes
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Alright! I got Mew from the truck! Here's how: Get the key from Professor Oak after you complete the national Pokedex and beat him in a battle. He uses Venusaur, Charizard, Blastoise, Snurffle, Deoxys, and Celebi all at level 100. Then, when you go to the truck, it is gone! Follow the tracks and you discover that it drove into the river! Run up to it and throw the key into the water. Then use one of your pokemon to destroy the doors on the truck. After you do, Mew pops out and is possessed by the spirits of the Keebler Elves! Blow him away by attacking with a Steel-type pokemon that knows electric attacks. After you beat him, capture Mew. Immediately after you do, Gary shows up and wants to battle, but then sees that you caught Mew and runs away screaming like a little girl.
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Mewwwwww!!!!!!!!!!! Has a secret to get it!!!!Catch all 380 (I rounded it to the nearest tenth)Catch Mewtwo last though!!! Then go to the elite 4 and beat them, go to the man who teaches you how to catch a pokemon (in viridian city) then go to bill and talk to him he'll say theirs somthing strainge going on in Cerilian cave. Their will be a man garding the cave he'll say no! No one is allowed in their is a strong force that must not be unlocked! Go to menu screen and click on master ball (if you have already used it to bad!)click on use the man will say oh I see....go forth great legand. Go to the same spot you found mewtwo only a smaller pinker creature will be there his level is 90.
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Like I said these stories sound pretty farfetched.
Here are the quotes
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Alright! I got Mew from the truck! Here's how: Get the key from Professor Oak after you complete the national Pokedex and beat him in a battle. He uses Venusaur, Charizard, Blastoise, Snurffle, Deoxys, and Celebi all at level 100. Then, when you go to the truck, it is gone! Follow the tracks and you discover that it drove into the river! Run up to it and throw the key into the water. Then use one of your pokemon to destroy the doors on the truck. After you do, Mew pops out and is possessed by the spirits of the Keebler Elves! Blow him away by attacking with a Steel-type pokemon that knows electric attacks. After you beat him, capture Mew. Immediately after you do, Gary shows up and wants to battle, but then sees that you caught Mew and runs away screaming like a little girl.
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Mewwwwww!!!!!!!!!!! Has a secret to get it!!!!Catch all 380 (I rounded it to the nearest tenth)Catch Mewtwo last though!!! Then go to the elite 4 and beat them, go to the man who teaches you how to catch a pokemon (in viridian city) then go to bill and talk to him he'll say theirs somthing strainge going on in Cerilian cave. Their will be a man garding the cave he'll say no! No one is allowed in their is a strong force that must not be unlocked! Go to menu screen and click on master ball (if you have already used it to bad!)click on use the man will say oh I see....go forth great legand. Go to the same spot you found mewtwo only a smaller pinker creature will be there his level is 90.
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Like I said these stories sound pretty farfetched.