The FC Caverns are an area accessible from the Techno Condominium.
Features
The FC Caverns is an extremely unique area among all of the worlds in this game, as it does not play out like a typical exploration-based RPG, but rather more like a movement-heavy platformer, akin to Super Mario World. The aesthetic of the area is very similar to that of the Alien Cellar, but considerably glitched-up and distorted.
The area is split up into two separate sections: the first one, which is a linear platformer to the left, and the second which is an area where Urotsuki climbs vertically, looping around the screen. Climbing to the very top will lead to a door to the Flooded Dungeon.