1990: "Holy Wars... The Punishment Due", Megadeth

1990 was a pivotal year for heavy metal. Thrash had already peaked, and was in the process of transitioning to death metal, but you wouldn't necessarily know it from the career peaks enjoyed by Megadeth, Slayer, Anthrax and Suicidal Tendencies.

Megadeth's Rust in Peace is frequently recognized as the best metal album of 1990, and few would argue that Dave Mustaine & co. ("& co." being, of course, whatever hired hands are currently in the band) have managed to scale these heights in the 20 years since. It's interesting to note that, whereas Metallica later went through a long period of treacly counseling before emerging with the colossally misguided St. Anger, in 1990 Dave Mustaine had only recently finished a twelve step program of his own; yet Rust in Peace would emerge as the band's most focused, grounded album.

Dave Mustaine has always had a more conventional sense of thrash than his former bandmates in Metallica, so Rust isn't exactly a left field art rock opus, it doesn't dabble in prog metal, and hell, the lyrics aren't even personal enough to qualify as cathartic... basically what we have here is a relentless riff fest fueled by paranoid politics and conspiracy theory lyrics. New arrival Marty Friedman is widely considered the best of all the "hired gun" lead guitarists Mustaine has acquired over the years - to the point where many feel his departure in 1999 was the final straw for Megadeth's artistic integrity - and for good reason: Friedman's solos are some of the best ever heard in the metal genre, and it's obvious that the new competition has Mustaine feeling reinvigorated.