First you have to unlock the marine resort then beat the training mazes on the right of the dojo. Then you can find Jirachi on the 23rd floor, Suicune on the 29th floor and Moltres on the 40th floor. Hope that helped! -Vanessa (aka Papita or Pokemon master)
Me! Lawlawlowkozl
Someone
There is no dungeon called final island, if you mean western cave then the answer would be mewtwo
48 floors
It's the Darkrai battle, as also seen in Pokemon Mystery Dungeon Explorers of Time/Darkness.
no
48 flloors
not sure maybe mew?
48 floors
after you beat the final boss
it depends it could range from 10 to 50 or even 100
There are 50 floors.