if you still have a master ball you can catch it but you can also save you masterball for the three dogs (entie, raikou and scucine) or ho-oh and lugia.
if you want help catchin mewtwo reply
um..its at level 70, not 80.....
Cerulean cave
Cerulean cave
you catch it in cerulean cave
You catch Mew-Two
The Cerulean Cave
mewtwo is in cerulean cave. the cave in in cerulean city, where misty's gym is. mewtwo in hard to catch, though.
If you mean, "Wobbuffet", you can catch it in Cerulean Cave.
Lot a thum in Cerulean Cave.
you can catch mewtwo at cerulean cave
cerulean cave works but its strong.
go to the cerulean cave and catch mewtwo
Cerulean Cave, Deepest point.