Go back to vermilion city and talk to the sailor who asks you for a ticket show him the tri pass or rainbow pass and you will be able to return to the islands.
Surf from Cinnabar island left there you can get in.
The Ultimate Horn in Leafgreen is not an item, it's a pokemon. Heracross. You can find him on island 6 in the paddock on left from the horn house.
You go to seafoam island from the right side not the left, you can figure out the rest from there
On cinnabar Island, to the left of the pokemon center, lies a "laboratory". If you go inside, then go to the right and enter the third door. Talk to the Professor there.
If you mean Pokemon FireRed/LeafGreen on the GBA, the mansion is in the top left corner of Cinnabar Island. (home of the seventh gym)
Yes, it's called breeding. On four island theres a day-care left two evolved pokemons that can have a baby pokemon.
It is on one island. You also have to go to the left of the island and surf upwards, theres the hot spring. Finally, go to the left of the hot spring and surf upwards.
she is in the berry forest on three island. you have to beat the bikers and travel all the way to the west of the island to get to berry forest, lostllie is at the top left of the forest
move left move right
after you catch mewtwo in Pokemon leafgreen/firered if you havent done so already you can explore the 7 islands.however if you already have done so there is really nothing left to do
you go to cinnabar island after beating the fifth gym.There the place on he left.3rd door on the right inside.Weird scientist in corner of the room.
You go to six island dotted hole at the ruins and use cut. Then you go through the holes in this order UP,LEFT,RIGHT,DOWN.