The Mystical Underworld or as many circles tend to call it the Underworld Kingdoms are a created plain of existence located below the original Earth, often known to the peoples who live there as the Mortal Realm. This plain is the home of every magical and mythical being that abandoned either from Launa's forced evacuation that was misinterpreted as a thoughtless attack before being overrun by the Nazis during World War II. Today, the Mystical Underworld is home to hundreds of thousands of magical beings that now call it home.
Formation of the Underworld
Its original started about during World War II when Nazi forces were spreading fast all across Europe and the Allied forces where coming in as well. The continent itself is littered with hidden lands protected by magic that prevents the humans from even being seen but that wasn't enough with the changing environment and loss of resources because of them being redirected in the war effort. Launa already forced to leave during the Invasion of the Netherlands, feared that if the Allies stumble upon the hidden lands they would be exploited or if the Nazis get their hands on them, either its people would be exterminated or exploited to win the war in their favor.
Having no other choice, she had to make the people leave their lands to prevent being discovered. But many do not want to leave because of their own stubbornness and over-confidence would prevent them from leaving. Launa forces them out of their lands and run as far from the warzone as possible. Many powerful warriors did stood up but only to attack Launa believing now that it was all a trick for her to get the magics since she's not part of their culture. Leading up to a massive misinterpretation of Launa's intentions. To the people who did leave, Launa destroyed the lands by burning them to the ground leaving no evidence for the enemy forces to find.
The powerful elders who guided the displaced led them all to Hölloch Cave in Switzerland and with their combined powers created a new world below the earth that is vast and more greater than the original lands they have lost. The mystical underworld is established from the Mortal Realm as a sanctuary and peaceful solution to be safe from the horrors of the old world.
There are various locations across the environment depending on what species or being lives there. What is amazing about these places in the Mystical Underworld is that they can range from vast mountain ranges to great forests and seas. To biologically active swamplands to the most inhospitable deserts. The Dragonlands, Great Forest, Kingdom of the Greys and many others covers the location.
The High Lords
The High Lords are the supreme authority of the Mystical Underworld and act as the law enforcement sector to protect the species from fighting against themselves or mortals who discover their location.