There's no way I could pick just one album to be the greatest metal album of the 1990s..
Simply because this is just
a few of the great albums released in the 90s:
Megadeth - Rust In Peace
Judas Priest - Painkiller
Pantera - Cowboys From Hell
Entombed - Left Hand Path
Metallica - Metallica (Can't believe nobody's mentioned this)
Cathedral - Forest of Equilibrium
Sepultura - Arise
Mayhem - De Mysteriis Dom Sathanas
Death - Human
Morbid Angel - Blessed Are the Sick
Carcass - Necroticism: Descanting the Insalubrious
Coroner - Mental Vortex
Pantera - Vulgar Display Of Power
Cynic - Focus
Death - Individual Thought Patterns
Carcass - Heartwork
Emperor - In the Nightside Eclipse
Dissection - Storm of the Light's Bane
At The Gates - Slaughter of the Soul