Leviathan

With the Crystal Rod in hand, you're ready to sail for the Mysidian Tower. It is located on a small island ringed with mountains in the sea north of Mysidia (and west of Altair). If you never brought your ship back to the inner sea after you trip to Castle Deist, you'll have to do so now. Unfortunately, when you approach the Mysidian Tower, you are attacked and swallowed by Leviathan.

Leila will permanently leave your party when the ship is attacked, so be sure to remove any rare or important equipment she may be carrying before you approach the Mysidian Tower.

Leviathan 1F

The Leviathan is a very simple and short dungeon. It consists of three floors, only two of which contain Monsters, and only three different Monsters on those floors. The most common of those Monsters is the annoying Bolt Fish, which absorbs Lightning and has no other Elemental weaknesses. Non-Elemental Spells like Holy and Drain are useful, as are basic physical attacks (especially from the Aquatic-killing Orichalcum). Bolt Fish have an annoying tendency to use Thunderbolt 8 on the party.

The Leviathan has a general Aquatic theme, and the other Monsters within—which often accompany Bolt Fishare vulnerable to Lightning. All are likely too powerful to take out with a multi-target Thunder Spell, though, so avoid healing the Bolt Fish by taking out one Sea Dragon or Manta Ray at a time. Both creatures have nearly identical attributes, except that Sea Dragons can use Tsunami 8, an effectively non-Elemental special attack that deals moderate damage to all Characters. In addition to accompanying Bolt Fish, you may run into groups of up to four Sea Dragons or five Manta Ray.

The "1F" of the Leviathan is a windy but non-branching path which may be intended to represent the creature's intestines. You'll find a Twist Headband and a Power Sash along the way. The Twist Headband is a great replacement for the Giant's Helm, granting a Strength bonus from the head slot to allow you to get an Agility bonus from Black Garb or Thief's Gloves. The Power Sash, on the other hand, is pretty underwhelming. It also gives a Strength bonus (which does not stack with other Strength bonuses), but it's harder to take full advantage of. It is decent back-row Armor, particularly if you have a bow user who can take advantage of the Strength bonus.

The Leviathan is the first place you've encountered damaging floor tiles, represented here as an orange-ish liquid. They pose little threat but do confer an opportunity on the party, albeit not so much in this one-time dungeon. If you ever wanted to level up a Cure Spell outside of combat, you can do that by repeatedly stepping on a damage tile and then healing up.

Leviathan 2F

The Second Floor of the Leviathan is a settlement of others who were swallowed up by the beast in the past. There are no Monsters to worry about here. Early on, you'll run into Ricard. Show him the Crystal Rod, and he will join the party. While he is a dragoon, he is a dedicated sword user (and not a polearm user as series veterans may expect). He has two pieces of Armor that grant strength bonuses, so you may want to swap one of those out, perhaps for an Agility bonus.

With Ricard in tow, you're free to speak to the various people stuck in the Leviathan. They'll tell you about how anyone who approaches the Mysidian Tower with a Crystal Rod is swallowed, and how you can escape to a ship via the Leviathan's mouth. The way is barred by a Monster, but that won't stop you.

Don't miss the Power Armlet, yet another Strength-boosting piece of Armor laying around the Leviathan. It can be found in the second northern room from the right, and is a potential upgrade for Ricard's Giant's Gloves. When you're ready, head to the stairs in the northwestern part of the floor to proceed.

Leviathan 3F

The Final Floor of the Leviathan is the inside of a large mouth, complete with multiple rows of teeth. The Monsters found here are the same as those on the 1F. The ship at the western edge of the floor (at the front of the mouth) is the exit, but you'll have to fight the blue worm in front of it to access it. You'll need to walk around the second row of teeth, either to the north or south, to reach it. Before you do, don't miss the two chests at the sides of Leviathan's mouth. To the north you'll find the Gaia Blade, a nice upgrade for any sword wielder, including Ricard. To the south, you'll find a Lightning-resistant Diamond Shield, which is guarded by a group of Red Souls. While these have traditionally been annoying Monsters, you suddenly have a whole host of Spells that will be effective. Holy or Drain will deal damage, but a good shot of Osmose can drain their MP pools entirely, denying them any effective offense.

The boss of the Leviathan is the Roundworm, a no-frills 2,000 HP physical Monster. It has six attacks that deal damage beyond anything you've seen, so Blink is a must for your front line. You can use the regular tactic of inflicting Curse to pierce its 100 Defense, but there is an even better option: the Blood Sword. While it will do little or no base damage, each hit will deal 125 damage and heal the wielder for the same amount. Or you can skip the process of eating away at its considerable HP entirely, and hit it with a decently-leveled KO spell to take advantage of its weak Magic Resistance.

Outside the Leviathan

You'll find yourself back in a ship, able to sail for the Mysidian Tower. You might want to head back to Altair and rest first, though, as it is a very long and nasty dungeon with multiple bosses.