Final Fantasy 1 Flying Fortress

Items: 93,715 Gil, Potion x2, Gold Needle x2, Cottage
Equipment: Protect Ring x2, Healing Helm, Venom Blade, Diamond Shield, Mythril Helm, Diamond Gloves, Black Robe, White Robe, Sasuke Protect Cloak, Shirt, Excalibur
Key item: Adamantite

This fortress has 5 floors, and the first 3 ones has lots of treasures. Your goal is to get to the top floor.

1st Floor

East Room : 11900 Gil, Protect Ring, Healing Helm
West Room : 21950 Gil, Potion
North Room : Venom Blade
South Path : Portal to 2nd floor.

2nd Floor

East Room : Diamond Shield
West Room : 13880 Gil
Northwest Room : Cottage, Mythril Helm
Northeast Room : Diamond Gloves
Southwest Room : Adamantite
Southeast Room : Black Robe, White Robe
South Path : Portal to 3rd floor.

3rd Floor

West Room : Gold Needle, 7550 Gil, Sasuke
East Room : 24035 Gil, Protect Cloak, Gold Needle, Shirt
Northwest Room : 14450 Gil, Potion, Protect Ring

There's a portal to the 4th floor located lower right of the west room.

4th Floor

This area is an endless maze, if you're heading in the wrong direction, so listen up. From the starting point, head east past large pits, then go south just before you reach the third one. Keep going down until you see a portal. Take it to the 5th floor.

From here, move on north for a boss fight.

Boss: Tiamat

HP: 2000 | EXP: 4245 | GIL: 6000

This thing's physical attacks can really hurt, not to mention the fact that it also has tri-elemental attack-all spells (Blaze, Icestorm, & Thunderbolt) Now have you black or red mages cast Steel on your fighters several times, followed once by Haste. Take note that Steel's effect is cummulative, so repeatedly using it on your characters can significantly boost their strength. As for white mages, have them use Shield 2 and NulAll.

Once you've done all that, have your fighters attack Tiamat. While the magicians provide support.

Warp out of the tower through the portal. Fly to Mt. Duergar, & give the Adamantite to Smyth the Smith. You'll get the "EXCALIBUR" after that.

Now head to the Temple of Chaos, and into the room where you fought Garland. Examine the black crystal to reveal a portal. Activate it to get to this game's final dungeon.