There is no 12 Island. There are 7 islands - that's why it's called the Sevii Islands.
on cinnabar island
On cinnabar island
its on birth island
There is no island 9 in either Pokemon FireRed or LeafGreen. Whoever told you this is very off. There are Seven Islands (Sevii Islands)
its to the left of the pokemon gym on cinnibar island
Growlithe is found in the Pokemon Mansion on Cinnabar Island in Pokemon Firered.
on cinnabar island
Beat the pokemon league.
There no Mew in firered.
you can get deoxys at birth island
in 1 island Pokemon center
On Cinnabar Island
On Birth Island
There is no island 9.
island 3
Deoxys
no