Just some similarities between Queen's song "Procession", from their 1974 album "Queen II" and the intro of Metallica's song "Blackened" from their 1988 album "...And Justice For All".
The Blackened intro was reversed for the album, and I reversed it again for the vídeo.

Note: I slightly panned the stereo mix in Procession for the guitar to be prominent in both channels instead of in just one.

All credits to them.