Final Fantasy 1 Mt. Gulg

Items: 29,180 Gil (Total), Antidote, CottageGold Needle, Potion x2, Tent
Equipment: Mythril Helm x2, Claymore, Mythril Gloves, Mythril Axe, Mythril Shield, Ice Brand, Flame Shield, Staff, Flame Mail

Here, just head west down the stairs to B2. The lava takes 1 HP away per step, but there are no random encounters while you're on it. There's no way you can completely avoid walking on the lava, so live with it while you're in this place.

In the next room, go west to get to the next area. But before that, I suggest heading into the first 3 doors from the entrance for several treasures.

1st door: 4,150 Gil, Mythril Helm
2nd door: 1,520 Gil, Claymore
3rd door: Mythril Helm, Mythril Gloves, 1,520 Gil, 1,760 Gil, 1,975 Gil, Antidote, 1,455 Gil, Tent, Potion (x2), Mythril Axe, Mythril Shield, 795 Gil, 750 Gil

At the next area, head east on the lava until you get to a staircase. Take it to a new room. Make your way southwest, down another staircase to a different section of B4. Proceed north into the room here for a couple of treasure chests, containing a "GOLD NEEDLE", & "2,750 Gil". Follow the path southwest for "1,750 Gil". The room further west contains an "ANTIDOTE", "7,340 Gil", "ICE BRAND", "880 Gil", & "FLAME SHIELD".

Head back to the fork, go south then up into a room containing a total of "165 Gil". The room northeast contains a "COTTAGE" & "2,000 Gil". Return to the fork once more, and this time go south. Pick up "1,250 Gil" & a "STAFF" from the room. Continue southwest down to B5.

The room at the west end of this area contains a "FLAME MAIL" armor. Go back to the entrance, then make your way to the southwest room for a boss fight.

Boss: Marilith

HP: 1200 | EXP: 2475 | GIL: 3000

First off, have your black or red mage cast Haste on your attackers, then followed by NulFire on your party. The Ice Brand does wonders here, so make sure your Warrior has it. The said weapon is capable of dealing as much as 150-200 HP worth of damage as the battle goes on. White mages should focus on healing. Also, put the Steel spell to good use if you have it.

Activate the portal to warp back to the world map. Go rest at Crescent Lake, then make your way back to your ship. Sail north, then west onto the river next to the continent of Pravoca. Onboard the canoe, continue northwest then take the lower fork south onto dry land. From there, just walk around the mountain into the cave.