Heavy metal guitar

"An essential technique aspiring thrash metal guitarists must master is the ability to perform fast single-note riffs and power-chord figures using only downstrokes. Two classic examples immediately come to mind: Metallica’s “Master of Puppets” and Megadeth’s “Hanger 18,” and there are, of course, many more great examples of relentless downpicked fury to be found in the world of metal. [...] To me, a relentless downstroke-driven pick attack is the only way to get certain riffs to jump out of the guitar with the aggressiveness necessary to make them sound as heavy and menacing as possible."