Master of Puppets may not be the best-selling heavy metal album of all time or even Metallica’s most popular record, but it may well be the greatest heavy metal ever recorded. Not only have all of its eight incredible songs withstood the test of time, they remain a benchmark for the thrash-metal genre.

Even though it’s hard to remember the music scene as it was way back in 1986, it’s still remarkable, if not miraculous, that music this powerful and aggressive could be irresistible enough to seduce so many music buyers to sounds that once would have sent them scattering.

Had there been no Master of Puppets, it’s likely that the entire ‘80s thrash phenomenon would have remained underground (even Slayer’s seminal Reign in Blood was simply too controversial to go mainstream), instead of a truly global and commercial proposition. Just compare it to offspring genres like black and death metal and that larger reach is all the more evident.

Master of Puppets didn’t just fall out of the skies into a favorable musical landscape, it disrupted the system through the sheer violent force of its revolutionary vision. Metallica and Master of Puppets simply would not be denied, and that’s why we’re looking back at this historic metal landmark with 30 facts to mark its 30th anniversary.