The trench is a unique location in Final Fantasy VI in that is it traversed entirely in Mode 7, as when riding a chocobo or piloting an airship. The player gets into random encounters along the way and at certain points must choose a path to swim down.
In the World of Ruin, the Serpent Trench still connects Mobliz and Nikeah, but due to the destruction of the world, it is now above water and is traversed on foot. The Cultists' Tower is situated on the Serpent Trench inside a ring of mountains.
World of Balance
Traverse the trench
Sabin, Cyan and Gau leap into the Serpent Trench after finding the diving helmet at Crescent Mountain Cave. Their travel is automated, the player just picking a direction at two points. Depending on the direction chosen, the party will find an underwater cave and can exit to continue on. The direction to find the cave both times is right.
The first cave is small with a treasure chest containing an X-Potion. The second cave is larger and requires the player to climb a flight of stairs and hit a switch to drain a flooded part of the cave, then drop down the hole the water drained from. The chest in this cave has a Green Beret.
Shortly after leaving the cave, the player will view a cutscene of the party arriving at Nikeah. If the caves are skipped, there is no appreciable time save beyond the time to go through the caves, so it is preferable to stop along the way for their treasures.
Mog can only learn the Water Harmony Dance by battling in a water area. If the player recruits Mog in the World of Balance, they can go through the Serpent Trench with him in the party to let Mog learn the dance. The easiest way to do this is land the airship at Nikeah and rent a chocobo, and ride it far east and south through the Doma region to Baren Falls - there the party can leap to the Veldt, leap into the Serpent Trench, and arrive back at Nikeah with their airship, Mog learning the dance on the way. Wherever they land the airship, they will always be able to get back to it, as Baren Falls is accessible from Nikeah by the time the airship is obtained. This dance is missable if the player progresses to World of Ruin without it.
In the Advance and mobile versions, if the player missed the opportunity to learn the dance here, they will get a second chance to learn the Water Harmony dance in the battle against Leviathan in the World of Ruin.
In the World of Balance, the Serpent Trench uses its eponymous track as a background theme, but in the World of Ruin, since it has surfaced into the Overworld, the World of Ruin's overworld themes ("Dark World" and "Searching for Friends") are heard when traveling it instead.
Behind the scenes
Serpent Trench was made by Tomoe Inazawa who was in charge of field graphics. The sea floor is dark rather than being fairly bright like the bottom of the sea in Final Fantasy V to make it more realistic and mysterious.
In terms of programming, the visual effect of swimming through the Serpent Trench is accomplished by putting the party in an airship that is then rendered invisible, and the vehicle is sent travelling over the Serpent Trench map in the same manner as when an airship flies an automated path on the overworld map.
serpent, or snake, is one of the oldest and most widespread mythological symbols. The word is derived from Latin serpens, a crawling animal. Snakes have been associated with some of the oldest rituals known to humankind and represent dual expression of good and evil.The