Anyway, here is how to do this glitch:
First off, this glitch is a combination of four glitches:
Mew glitch
Extended Mew glitch
Level changing glitch
Shiny Ditto glitch
You need the following things:
- A G/S/or C and R/B/or Y version
- A way to trade pokemon
- A Shiny pokemon that only knows Mimic.
- A Pokemon with an attack increasing move with a Special of 21. (I use Scyther with Swords Dance)
- A trainer that's line of sight stretches all the way across the screen
- Any trainer that hasn't already been battle that isn't in the same route as the previous trainer.
- A pokemon that can fly, teleport, or dig, or an Escape Rope.
The theory is this: Since the Shiny Ditto glitch requires the use of Transform on both Pokemon and Mew learns Transform at level 10, couldn't the same rule apply to get a Shiny Mew as it does for Ditto?
It seems probable, but now how to get Mew at Level 10+ when it appears at Level 7 in the Wild. This is where the Extended Mew glitch comes in.
The extended Mew glitch is using a Ditto to transform into a Pokemon you've trained with a Special Stat that reads 21. Next, we get into the Level changing glitch.
When you or the opponent changes the opponent's attack stats, (Growl, Swords Dance, Sharpen, etc.) the level of the Mew will change depending on the final attack strength.
Every Pokemon has an attack strength of 7 at the beginning of a battle. There is a range of 1 - 13. You can go down 6 (that's the lowest) or up 6 (the highest) and anywhere inbetween. In the video I have Ditto use Swords Dance twice. That increases its attack strentgh by 4. 4+7 is 11 which is the level of the Mew I'll fight.
Okay, now iniate the final part of the Mew glitch, returning to the route you started and fighting Mew. Before you fight Mew, make sure the Shiny Pokemon with Mimic is in the front. When you return to the route, the Start menu will pop up, exit it and a level 11 Mew will appear.
Now, use Mimic and take Mew's Transform. Make sure Mew uses Transform to transform into the Shiny Pokemon. If it uses Pound, use an item to waste a turn. DO NOT Transform into the Mew or switch Pokemon. Keep using items until Mew Transforms into the Shiny Pokemon. Now transform into each other a few times and catch it.
I'm not 100% sure why the games reads it as a Ditto, but this is my best guess: When a pokemon is in "Transformed" mode normally only possible in the wild from a Ditto, and you catch the "Transformed" pokemon, the game automatically reads the "Transformed" pokemon as a Ditto.
Not a good explination I know but still.