Metal suffered a rather severe comedown in the 2000s, with bands such as Trivium and Bullet For My Valentine thrilling their own dedicated fan-bases, but never truly wooing the mainstream. Fortunately for metalheads everywhere, the genre's head was kept above the water by nine masked men from Iowa. Slipknot first gained attention on the back of their gimmicky appearance, but had well and truly proven their credentials by the release of Vol. 3. The album is a seething, screaming mass of discontent, and proved that the band had worth far beyond their distinctive masks. Decade Defining Track: Duality