Great Sea Trench

The Great Sea Trench (大海溝) is a location in Final Fantasy V located in the merged and second worlds, although only accessible on the merged world. It is where one of the tablets needed to unseal the twelve legendary weapons in the Sealed Castle is located, as well as the "Great Dwarven Kingdom".

Story
After obtaining the submarine at the Catapult, the Warriors of Light head into the Great Sea Trench, a giant volcanic underwater cave. At the bottom, they find their third tablet, but are attacked by three of Exdeath's demons, Triton, Nereid, and Phobos. After defeating them, they obtain the third Tablet and the ultimate Time Magic, Meteor.

At the end of the game, when the four Crystals are restored, the Crystal of Fire is placed here.

Strategy
All of the random encounters in this dungeon are undead. Therefore, one easy way to get through is to use the Bard's Sing ability to cast Requiem continuously in each fight. This song does several thousand points of damage to all undead monsters, and uses no MP. A Geomancer is also a useful addition to the party as not to take damage from the lava floors while traveling.

Shops
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Weapon Shop

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Armor Shop

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Enemies

 * Unknown (#168)
 * Unknown (#169)
 * Unknown (#170)
 * Unknown (#171)
 * Unknown (#172)
 * Triton (Boss)
 * Nereid (Boss)
 * Phobos (Boss)

Music
The background theme that plays at the Great Sea Trench is called "Beyond the Great Blue Seas".