Pitting four classic discographies up against each other, we have ranked every album from thrash's 'Big 4' from worst to best.

The collective studio output from Metallica, Slayer, Megadeth and Anthrax totals 49 original albums, with Megadeth having released the most at 16.

Ranking these independent discographies is a difficult enough task as each band possesses a great deal of high-value material and we're not just talking about the classics — each group has delivered serious quality in the 21st century as well, which firmly asserts their right to lay claim to being in the hallowed 'Big 4' grouping.

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Of course, time is always the ultimate test and while some records that aren't stone cold classics have held up quite nicely and a lot of the stylistic fuss doesn't really matter anymore. How, more than 30 years later, could it at all be heretical for Metallica to abandon thrash and usher in an entirely new era of hard rock with the Black Album? So many of the group's fans weren't even born when that album came out, so there's it's hard to take such a shift personally when you weren't there to hold the old style so close to your metal heart.

Anyway, let's get back on track and dive into Every Thrash 'Big 4' Album Ranked From Worst to Best, directly below. There's certainly a lot to discuss!

NOTE: Lulu has been omitted from this ranking as it is a collaborative record.

Album descriptions by Philip Trapp, Ed Rivadavia, Jordan Blum, Ayron Rutan and Joe DiVita.

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