The son of crimeboss Silvio "Silvermane" Manfredi, Joe Manfredi himself was the costumed supervillain known as Blackwing, but after his defeat by the Thunderbolts as a member of the Masters of Evil VII, Joe Manfredi decided to retire as a costumed supervillain, and stay on as crimeboss. He founded his own super-army: Heavy Mettle 
Several members of Heavy Mettle were later incorporated in the Secret Initiative under Norman Osborn's reign. During the mission in taking Prison 42 from the remnants of King Blastaar's army, most of the members were killed.
- 3 appearance(s) of Heavy Mettle (Earth-616)
- 1 image(s) of Heavy Mettle (Earth-616)
- 7 member(s) of Heavy Mettle (Earth-616)