The G.I. Joe team's original heavy ordnance trooper, Heavy Duty—real name Lamont A. Morris or Hershel Dalton, depending who you ask—has served as a valuable member of the team with his brute strength and heavy firepower since its earliest days. Though some would say his cousin Roadblock has eclipsed him since "H.D." brought him onto the team, Heavy Duty still holds his own as a heavy weapons specialist in every metric... bar one. Where Roadblock is a gourmet chef, Heavy Duty should never be let into the kitchen — he can't even make ramen noodles right.
Sergeant Lamont A. Morris was a heavy machine gunner of the United States Army, and the cousin of Sergeant Marvin F. Hinton. During his time in the army he was assigned to a classified, and tedious, jungle posting, where he had little to do and mostly spent his time playing a video game designed at Fort Aberdeen for Army team-building, provided to him by his cousin who was stationed there... though Morris's focus was less on teamwork and more on racking up his own kill-count. While stationed there, he was selected for the newly formed G.I. Joe team, and as such was declared legally dead, with his family being informed that he had laid down his life to save his teammates after being surprised by superior numbers.
As part of the team, one of "Heavy Duty"'s first missions was to do "recon" on four outlaw tax-resistors who were holding up a bank; though he took his machine gun in with him, his immense strength allowed Heavy Duty was able to subdue three of them without firing a shot, but the fourth escaped in an SUV and Heavy Duty and General Hawk were forced to pursue him out into the Nevada desert. The two tailed their target to a mysterious, abandoned military installation that the outlaws were using as a base, before returning to the motel where he was introduced to the remainder of the team: Duke, Scarlett, Stalker, Snake Eyes, Breaker, and Rock & Roll. When Snake Eyes turned up the volume on a TV news feed, Heavy Duty realised that the hijacked National Guard convoy that it had been reporting on was carrying a TOW missile launcher, leading Hawk to realise that Chimera was behind the attack; Chimera soon used the missile launcher to attack an armored car full of money, proving their theory and leading Hawk to send the team, including Heavy Duty, into action to intercept Chimera at the base. Arriving within six kilometers of the target, Heavy Duty and the rest of the team parachuted out of their C-130, and hiked to the base. Arriving at the compound at dawn, the team discovered a hidden entry ramp by the marks left in the sand; when all the team's communications went down, Heavy Duty advised against trying to storm the compound, but was overruled by Duke on the basis of the need to rescue Chimera's hostage.
While Scarlett surveyed the compound, Heavy Duty covered her with his machine gun, and descended into the underground base with the rest of the team after Scarlett found the switch. When Chimera's mercenaries clashed with the team, Heavy Duty and Rock & Roll provided fire suppression for the rest of the team, allowing them to advance. Cahill—killing himself with a grenade rather than be captured. The threat dealt with, the team headed to the command center where Chimera was just in time to find Scarlett, Snake Eyes apparently having sacrificed himself to kill Chimera (though he soon proved to still be alive). While the team failed to prevent Chimera's "Poison Pen" plan from activating, Breaker managed to stop "Poison Gas", and on turning on the lights the team realised that the "Pit" they were in might make a suitable base for them. The team would go on to meet with the original "G.I. Joe" Colton, who gave them his approval.When a grenade Scarlett had been intending to throw was knocked out of her hand and to her teammates' feet, Heavy Duty pulled Rock 'n Roll off the grenade from where he had been covering it with his body, allowing Duke to kick it back over to the mercenaries; while the team regrouped, Heavy Duty griped that he now had to respect Rock despite not even liking him. In a final push, Heavy Duty once more provided suppressive fire, allowing his teammates to get close enough to kill the mercenaries, with the last—
Shortly after their first mission, Heavy Duty, Scarlett, and Duke were dispatched on a mission to Spain to bring in several men connected to the Borovian genocide. After Scarlett dealt with a Borovian Liberation Front cell who had recognised her as a spy, Heavy Duty and Duke intervened to help her in discussions with the CIA, and stood guard while negotiations took place. Heavy and Breaker stood guard while Scarlett and Rock & Roll infiltrated the office of Portero Moderno; after Scarlett got in a fight with the proprietor, she was forced to throw a computer — set ablaze by a thermite charge — out of the window so that Heavy Duty could get the hard drive out of it. While Scarlett and Breaker went through the drive's files, Heavy Duty attempted to calm down the Joes' captive Saeva Indignatio conspirators when they started fighting, and when the Joes travelled to England to neutralise terrorists that had taken control of the U.S. embassy, Heavy defended Snake Eyes' use of a sword to the British troops. During the mission, Duke and Heavy Duty entered the embassy through the rear entrance; Heavy broke down the steel door with a sledgehammer, which he used to knock out members of the terrorists' team stationed at the back door. When terrorist leader "Esau" threatened to arm his dead man's switch for the nuclear device within the embassy, Heavy Duty advocated rushing the terrorists; however, they didn't have to, as Hawk and Snake Eyes managed to deal with them without the nuke going off.
After G.I. Joe had settled into the Pit, Heavy Duty continued to enjoy playing the "Sigma 6" video game developed at Fort Aberdeen, despite Hawk giving him orders not to play it over an open internet connection. During one of his game outings, his cousin Marvin Hinton—still mourning his cousin, who he believed to be dead—spotted Heavy Duty's avatar in-game; though Heavy Duty immediately disconnected, Hinton was left confused, and ended up tracking Heavy Duty's I.P. back to the Pit, which he broke into. During a break in Hawk's interrogation of Hinton, he chewed Heavy Duty out for disobeying orders, not knowing what to do with the infiltrator; in response, Heavy Duty suggested that Hawk invite him to join the team, suggesting his in-game callsign of "Roadblock" as a codename.
Heavy Duty was one of the Joes present aboard a US Air Force cargo plane, having been tipped off by one of Colossus Word Security's private soldiers that his team would attempt to steal a prototype missile. However, the team's leader, named Monk, refused to surrender and activated the weapon, blowing a hole in the plane. Heavy Duty and his teammates were able to parachute to safety.
After G.I. Joe agent Chuckles was sent undercover, Heavy Duty was part of a fake sting intended to sell Chuckles's new employers on his loyalty, and wore exploding blood packs designed to detonate when the undercover Joe fired blanks at him.
After Bazooka was killed by a Cobra agent, Heavy Duty was one of the Joes that gathered to memorialise him. Later on, Heavy Duty was present while Brainstorm briefed the Joes on Cobra's M.A.S.S. device.
Heavy Duty served in the Nanzhao conflict alongside Mayday, with their team escaping the region shortly before it was devastated by nuclear weapons; Mayday would later credit Heavy Duty with saving her life in Nanzhao.
After G.I. Joe was reestablished to combat the Cybertronians, Heavy Duty (now going by the name “Hershel Dalton”) was one of the Joes stationed on Governor's Island. When Ian Noble infiltrated the Joes' HQ to free the captive Kup, Heavy Duty, responded alongside Flash and Mayday. However, even with the help of M.A.S.K., the Joes were unable to stop the British agent and the Autobot from escaping.
After the Revolution event, Heavy Duty was assigned to a new team under the command of Mayday, alongside Flash and Quarrel. Their first assignment brought them to Verenya, Schleteva, where they were attacked by creatures resembling Dire Wraiths. The Joes were then saved by Rom, who revealed the seeming Wraiths to be mutated humans that weren't fully infected. Sadly, Heavy Duty had already killed some of the victims in the fight. The team joined forces with the Space Knight to investigate what was creating the Wraith mutates. They followed the Wriath energy trail to an underground bunker, where they discovered the body of an Oktober Guard officer whom Quarrel identified as Shturmovik. As they continued their search of the bunker, the group ran into Ian Noble, the Action Man, engaged in a battle with Garrison Blackrock over the mysterious artifact called the Talisman. However, their squabble was soon interrupted by the arrival of the rest of the Oktober Guard, led by Major Bludd. As the Guard attacked the disparate groups, the Talisman activated, mutating Quarrel, Flash, and Heavy Duty. The three attacked the rest of the heroes, but Rom managed to subdue them.
The mutated Joes and civilians were later restrained and taken by the Action Man Programme in order to be cured.
Once the Revolutionaries had recovered the Talisman and Garrison Kreiger, the Wraith-mutates were taken to an Onyx facility in Buenos Aires, where Blackrock studied the effects of the artifact. A group of Joes, including Roadblock, were also present. Roadblock stressed the seriousness of getting his cousin, and the rest of the mutates, cured. However, their efforts were interrupted by the arrival of Baron Ironblood and his allies. During the battle, Ian Noble freed the Wraith-mutates in order to distract Doctor X. They soon rampaged across the facility, attacking both Ironblood's forces and the heroes. Luckily, Blackrock was able to use his Cybertronian programming to link the Talisman with the Autobot Metrotitan, sending out a wave of energy that reverted the mutates back into humans.
- Heavy Duty was originally introduced as a substitute for Roadblock in IDW, since the name "Roadblock" was unavailable due to trademark reasons. Roadblock later appeared, with no one commenting on the matter, and it appeared that "Heavy Duty" had merely been renamed to Roadblock. It wasn’t until G.I. Joe vol. 3 that they were officially retconned into two separate characters.
- In G.I. Joe vol. 3 #11, Heavy Duty was given the name "Lamont Morris", the same as his 1986 incarnation. However, in Action Man: Revolution, he was identified in a caption as "Hershel Dalton," the name used by the Rise of Cobra and Renegades incarnation. According to John Barber, this change was actually a Hasbro mandated one. An in-universe reason for the name change has yet to be given (making it possible that it's a simple retcon), but Barber offered the possibility he might have had to go under a new name after G.I. Joe was reinstated.
- Heavy Duty's video game avatar in G.I. Joe vol. 3 #11 is based on the character's G.I. Joe: Sigma Six incarnation.
- "Bullet Points" letters page in the back of G.I. Joe vol. 1 #9. Admittedly, the letters page also suggested that an IDW incarnation of Roadblock would speak in rhyme, so don't believe everything you read.
- John Barber on Twitter: "We had him as Lamont in GI Joe and Hasbro asked us to change his name when he showed up in Revolutionaries."
- John Barber on Twitter: "Maybe unusual and special circumstances dictated he used a different name after GI Joe went public."