LogFAQs > #979562645

Black Sabbath - Paranoid
Iron Maiden - The Number of the Beast
Metallica - Master of Puppets
Slayer - Reign in Blood

Any serious metal rushmore basically requires a Sabbath album, and Paranoid has both the big hits and some crazy influential songs (in metal circles Electric Funeral and Hand of Doom are almost as influentialy as that album's big 3). Number of the Beast debuted the Dickinson era, was pretty controversial when it came out and is still a massively popular and influential record. Metallica is almost as obligatory as Sabbath (though KEA and the black album can be argued to be here over Master). Slayer in the last slot is there mostly to represent extreme metal.

There are way too many HMs, most of them in genres not repped above (death, black, power, prog, etc.), to even bother listing so I will instead say yeah Judas Priest should probably be here but one problem: unlike with the bands above, picking one album with them is excruciatingly hard. They legitimately have half a dozen albums that could be on the rushmore.