The Underground Cavern (地下洞窟, Chika Dōkutsu) is a dungeon found in Mary Skelter: Nightmares and Mary Skelter 2. It acts as a bonus dungeon that can be accessed during Chapter 7 after getting all three Mary Gun upgrades and can be finished after the Good Ending in Nightmares. It is the dungeon for Chapter 1 in the second game and is the home of the Blood Maiden Hameln.
Mary Skelter: Nightmares[]
Appearance[]
The area is covered in mouths that move of their own accord. Barred walls are frequently seen throughout the dungeon. The ground will occasionally have mosaic-like glowing patterns. The color palette is almost entirely dark blue, with the mosaic ground having portions of yellow and green. Its track is "Hither and Thither at the Bottom," and features exotic-sounding stringed instruments along with a flute melody, alluding to Hameln's fairy tale.
The Mary Reverser needs to be used to cross the gap of the third floor of the City Streets in order to reach the Underground Cavern. Once there, only the first floor is accessible to the player, where they can fight and gain Hameln as an ally. After the Good Ending of the game, the door will be unlocked, and the player can proceed, eventually leading to the Metropolitan Office.
In the original version of Nightmares, entry to the Underground Cavern is located in the second area of the City Streets. In this version, the map is much larger, sporting a 100x100 tile map, with the exception of area 1, (which is 15x15) where you fight Hameln and area 5 (50x50), which is unlocked after defeating the nightmare. This version does not include the Metropolitan Office, nor does it mention Otsuu. It simply ends on a cliffhanger. Another difference is that the soundtrack is called "The floor here".
Enemies[]
Maps (Remake version)[]
Maps (Original version)[]
Mary Skelter 2[]
Appearance[]
Much like the Nightmares version, the underground cavern is an area below city streets and it may stretch further underground. It boasts the same design, with a slightly different color palette, however, it is much smaller in size, due to not being grown by Otsuu. It is yet again the residence of Hameln, who has made a home of an old railway station, boasting a great view up to the ground layer and even a waterfall. This place will later be renamed to the New Liberated District. Concept and gameplay wise, the cavern has tunnels that lead to City Streets, Aquarium Ruins and Dorm, as seen on the overworld map and in how you progress to those areas in-game.