Norwegian symphonic black metal
band. While middle-aged people
generalize their lyrics as dark and angsty, unlike The Beatles
, they have the ability to cover more than one topic in a single album, including poetically challenging extremist conservative religious fanatics, the definition of morality, telling a narrative of Satan's assistant, and several more if you understand Norwegian.
Occasionally their music videos or lyrics contain unjustifiably objectionable material, but I interpret that this is their message to their fans not to become mindless followers of their band.
If you had to mass-generalize Dimmu Borgir, you'd have to call them a cross between heavy metal and classical.