https://www.youtube.com/watch?v=j8o86P-nTtM Good thing that it's just a game, or is it?.
Demonology Explained https://www.youtube.com/watch?v=02LYLz1y6x4
Paradise Lost | The Story of Lucifer You Were Never Told https://www.youtube.com/watch?v=-dS0ZRKEonk
The Underworld is quite a peculiar concept, a lower level or realm of beings of darkness & chaos, etc.
https://en.wikipedia.org/wiki/Underworld#By_religion
https://www.greekmythology.com/Myths/Places/The_Underworld/the_underworld.html
https://en.wikipedia.org/wiki/Underworld#Underworld_figures
https://www.getty.edu/art/exhibitions/ancient_underworld/inner.html
Quatermass_and_the_Pit is a fantastic Sci-Fi movie about some ancient alien insectoids that either crashed or landed on earth. It's an interesting take on nefarious beings emerging from the underworld.
https://en.wikipedia.org/wiki/Quatermass_and_the_Pit_(1967_film)#Plot , https://archive.org/details/quatermass-and-the-pit
In the War_of_the_Worlds_(2005_film), it is revealed that some nefarious ancient Martians sent some remote controlled ships to crash & hide deep underground until they are needed to be activated for a future war on earth. Once they boot up their attack, some Martian pilots are transported or teleported into their long dormant underworld vehicles.
https://en.wikipedia.org/wiki/War_of_the_Worlds_(2005_film)#Plot
