Heavy Mettle are a group of mercenaries that wear power suits and use high-tech weaponry. The group consist of Firestrike, Riot, Barracuda, Blackwing, Warbow and Stronghold and they were hired as muscle for Joe Silvermane's operations. Silvermane was selling high-tech weaponry from AIM to gang members and the New Warriors wanted to shut them down. Dalton Beck was dating Turbo of the New Warriors and Musashi had no idea that Dalton was Firestrike, the leader of Heavy Mettle. Dalton was trying to get close to Musashi so he could steal the Turbo armor but was conflicted because he started to have feelings for her. Aegis got the name of the arms dealer that was supplying the gangs with the weapons but Heavy Mettle was waiting to ambush them when they arrived to the warehouse in the Williamsburg neighborhood of Brooklyn. Speedball charged towards Heavy Mettle and a fight ensued between the two teams. Heavy Mettle survived their first encounter with the New Warriors and escaped. Turbo would discover that Dalton was really Firestrike and he decided to turn over a new leaf and tell the New Warriors who was the man behind the entire operation. Nova would disguise himself as Firestrike and meet the rest of Heavy Mettle at a warehouse in Brooklyn. Stronghold tackled Firestrike and the rest of Heavy Mettle entered the fray. The battle was short and sweet but they told Firestrike they didn't mean to hurt him and considered the assault a practice session. Heavy Mettle raided a Baintronics weapons convoy in the Adirondack Mountains in Upstate, New York where the New Warriors were waiting. Riot fired a sonic blast that caused the driver of the convoy to lose control and topple to the ground. Stronghold used her super strength to stop the careening truck and rip the door off its hinges. Stronghold heard a sound and Namorita took her down with a thunderous punch. The rest of the New Warriors appeared and engaged Heavy Mettle in combat. All members of Heavy Mettle were defeated and Dalton Beck was placed in the witness protection program.
All the members of Heavy Mettle except Firestrike would join the Initiative
and they are selected to join the Shadow Initiative
brings in a bunch of D-list villains and other Initiative members they feel are expendable into the Shadow Initiative. This group was the first wave of Initiative members to assault a prison in the Negative Zone
called 42 that was taken over by Blastaar
and his army. This group acted as cannon fodder to soften up Blastaar's forces before sending in the big boys to clean up. Most of Heavy Mettle were killed in the assault but Warbow survived. However, Warbow is killed when Norman Osborn
and the rest of the Initiative attack Asgard