In this latest Loud List, we count down our picks for the 20 Greatest Metal Riffs of All Time.

Timelessness may be the most important aspect of an iconic riff. No matter how many decades pass, metal's greatest leads feel bigger than everything that's come after. Most of these riffs belong to classic acts, though we do delve into the 21st century for a modern masterpiece.

No metal riffs list is complete without the great Tony Iommi. Black Sabbath's godlike guitarist has written more monstrous riffs than anyone else, even with two of his fingers partially chopped off. This list could easily be top loaded with Iommi's parts, but we narrowed his riffography down to four essential pieces for this Top 20.

Iron Maiden also have multiple entries in this video, as do the metal gods of Judas Priest. Both bands have massive portfolios of guitar parts, but can you guess which heavy metal anthems made the list? Modern titans of groove like Pantera and Korn found a way to turn simplicity into an energy that completely changed the direction of metal from the '80s era into the '90s. You'll see which genre-defining moments were able to crack out Top 20.

Check out the 20 Greatest Metal Riffs of All Time in the video above!

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