Metal fans around the world saw their dreams come true in recent years when Metallica, Megadeth, Anthrax and Slayer hit the road together as the Big Four. Old rivalries were put aside in order to fill stadiums with one of the biggest shows in metal history. There's only one way to top that: go back a generation and bring Black Sabbath, Iron Maiden, Judas Priest and Motorhead together on one stage. Iron Maiden alone can pack arenas, but the combined power of all four bands would make for a truly memorable bill. Things didn't go so well on 2005's Ozzfest tour, when Iron Maiden had to play before Black Sabbath – but seven years is a long time, and they should be able to pull it off. If for no other reason, this tour should happen so that VH1 Classic host Eddie Trunk can be the happiest man alive.