As the translation of the Japanese name is unofficial, it may contain errors.
Overview
The Black Fog (Japanese: 黒い霧, Kuroi Kiri [lit. "Black Fog"]) was a mysterious mist that appeared several weeks to months before the start of Lost Kingdoms. It swallowed up a forest in Bhashea, then a lake, then an entire village, before swallowing up the whole kingdom. Bhashea had not been heard from in weeks by the start of the game and arrival of the Black Fog at the gates of Alanjeh.
Monsters come from the Black Fog and attack people who enter it. Additionally, Lord Unther saw a woman in black in the fog amongst the monsters in Blessoon, and postulated that she was their leader.
In the Burial Grounds, the grave of the Cursed King Beria, also known as the Explorer King, implies that the Black Fog phenomena has existed long before the game starts.
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