The airship.
The Rat's tail. (don't have the Rat's tail, tomorrow, check back in about 8:00 or so to view Get the Rat's Tail in Final Fantasy I, kay?);
, I can't remember which one it is, but, I can give you this hint (well, actually 2, but) The room will be going straight down. There will be no monsters.
 Now head in those stairs and go on into this room , and keep on walking, (boring) soon you will encounter a big Dragon. Talk to him, he will say something bout your Rat's Tail and upgrade your people. Read the tips for descriptions of your new jobs.
Get what you will need.
Once you have these, head to some narrow strips of land about a few inches big with holes in them.
Once you find it, then head down the Narrow place until you hit some stairs.
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