you must have mystery gift to do it... also you need to have 386 shyny's.. (that means from bulbasaur to deoxys)..........
Yes on the seventh island.
The secret is the Pokemon unown.
You go to island 6, turn right at PC, go down the stairs and direct forward.
You must trade a Graveler to another GBA game.
i don't know about a mystical pokemon, but if you solve the puzzle in Tanoby Key (which is the cave in seavault canyon) Unown appear in the Monean ruin. Solve the puzzle in Tanoby Key by putting all the boulders in the holes.
there is only a ruin valley which is on six island the south of the island to be in fact.
Ruin valley is the southern portion of six island.
There is a link to the plot guide below.
you have to solve the puzzles and capture or catch all types of unown
On six island a ruin maniac in ruin valley has a golem.
a valley on six island
Its in the southern portion of the island in ruin valley.
the island of ruin
Ruin Valley is a location exclusive to Pokemon FireRed and LeafGreen. Ruin Valley can be found in the south of Fortune Island in the Sevii Islands.
Ruin valley is on six island on the southern portion of it and to get to six island you must beat the elite four get the national dex and deliver the ruby to celio.
South part of six island.
rainbow island