Mewtwo is in the Cerulean Cave near Cerulean City. To get to Cerulean cave though, you have to get surf, and complete two achievements such as hatch an egg and delete the Elite Four.
Have it traded to you from a Firered/Leafgreen.
get every Pokemon in the game then go to mystery cave and catch it
Mew Mew2 Zapdos Moltres and Articuno
after you beat the Pokemon league go back to where you battled misty and to your left there is a Pokemon ranger guarding a cave then you talk to him and he will let you in
the Pokemon are pigey, mew2 first of all there are more than that and second pigey is not lengendary
MewTwo can be found and caught in Cerulean Cave. Hint save before you battle him and if you fail you can try again.
well you passed it when the credits go up and you can go get the legendary mew2 and the rest is the bonus storyline that's it
Mew 3 doesn't exist and the only Mew-anything you can find is mew2 at the back of Cerulean Cave.
mew2 is the rarest
from a gba game.
palpark mountain parts
get the ruby and the Sapphire gems from 4and 6 islands . the go to ceroolien cave.you can find mew2 in there.