Metallica - Call of Ktulu 🤘🏻
Written by James Hetfield, Lars Ulrich, Cliff Burton and original Metallica guitarist Dave Mustaine (who left before the album was recorded), this instrumental was inspired by the story The Call Of Cthulhu by H.P. Lovecraft. The author is a big influence on Metallica - his work also inspired their song "Thing That Should Not Be."
In the book, the story says that mentioning the name Cthulhu (Verbally or written) will bring him closer. That's why Metallica used the name "Ktulu" and not "Cthulhu" - for fear of the beast.
For more references in metal music: https://www.kerrang.com/features/thy-horror-cosmic-celebrating-metals-obsession-with-h-p-lovecraft/
And the graphic novel by Alan Moore: Providence.