Pleaselog inorregisterto add a comment.
In order to catch a wild Blastoise you need to perform the Mew glitch as usual, but instead of battling the swimmer in the Cerulean Gym or youngster on route 25, you need to find a group of 4 trainers standing in a line on route 8 and battle the 2nd trainer from the bottom on the line with 3 Meowths. Then continue the glitch as normal and a wild Blastoise should appear instead on Mew. If you’ve already fought this trainer, you can also catch a Pokemon and train it until it Special stat is 28 (there will be a different Pokemon otherwise) and battle a ditto which copies your special stat when it uses transform. Defeat it and continue the glitch as normal to encounter a wild Blastoise.
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Hope this helps.