Okay, I'm sure I'll get pounded on for not already knowing this stuff, but not too long ago I re-read Hellboy and the B.P.R.D.: 1954 - The Black Sun #1-2, and I'm currently re-reading the tpb collection of Sledgehammer 44.

Anyway, looking into "vril" on a Google search, and the article it turned up for "Vril" (https://en.wikipedia.org/wiki/Vril) touches on so many things that I've already read in Mignolaverse books that it's quite thought-provoking (for me, anyway).
Among other things, it references a 19th century novel by Edward Bulwer-Lytton titled The Coming Race with a subterranean world populated by a race called the Vril-ya (who themselves are descendants of a race called the Ana). The Vril-ya have access to a source called "Vril" which had very destructive potential.
Later in the article it talks about a "Vril Society" in 20th century Germany as well as a link to a book called Black Sun: Aryan Cults, Esoteric Nazism and the Politics of Identity.
Another Wikipedia article on Nazi UFOs (https://en.wikipedia.org/wiki/Nazi_UFOs) also suggests what we had in Hellboy and the B.P.R.D.: 1954 - The Black Sun.

I know the Vril technology played a part in Lobster Johnson: The Iron Prometheus as well as in Sledgehammer 44 and Hellboy and the B.P.R.D.: 1954 - The Black Sun, but where else has it played a major part?