An ancient ruin, deep in the Sandflow Caves. It is here that the last surviving Manta had their last stand, and where they were utterly defeated by the calamity from the skies...

Nowadays, their spectres roam its chill halls, bewailing the injustice of their demise, longing for vengeance. Or something dramatic like that. Either way, it's a secret dungeon! You should be proud to have found it!

Encyclopaedia description

The Miasmal Citadel is an optional dungeon in the MARDEK series. It houses the first superboss of MARDEK Chapter 3: Keystones, Annihilator:Karnos.

To access the Miasmal Citadel, you have to defeat the Bandits that Muriance sends after you when you give him the ★ Runestone Fragment. They drop a ★ Bandit Key which can then be used to open the warehouse in the Aeropolis slums. The shopkeeper here sells the ★ Eldritch Key which unlocks a door in the antechamber of the Dark Temple where Gope is. The door will lead to a separate part of the Sandflow Caves, which leads to the entrance of the Miasmal Citadel. You will have to put all the Miasmal Chalices, obtained from the Dark, Water, Fire, and Earth Temples on the vacant pedestals here. The portal to the "main" part of the Citadel will then activate. There is also another 2-way portal to the Sun Temple here.

Monster formations

Random (everywhere except entrance and boss area):


Treasures found

Branching room


Left room


Right room

Beyond the Gem Door

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