Eh, dumb thread. Look up D&D dark elf aesthetic or maybe the one from Star Wars' Galactic Imperium side? WH40K had several different styles to pick from, like Chaos, Necrons or Dark Eldars (orks too dumb to qualify). Even most Daedra from Elder Scrolls franchise would fit here. Mostly minimalistic, monumental, and subdued in tone on one side and in-your-face spiky and bloody on the other. Lots of shiny black and deep purple or toxic green, usually. You can reinvent the wheel yourself or notice what presses the right buttons from the content that already exists.