The Hulkbuster armor was revealed in Seeing Red. Tony created this armor some time before and he used it to break into the Project Pegasus facility to upload the Technovore virus and deal with the second Crimson Dynamo, resulting in its destruction.
It's used yet again in Uncontrollable. When the Hulk was rampaging around at an AIM base, Tony activated the Buster armor and tried to stop him, but without any success. He was approached by a Controller-possessed Rick Jones who put one of his disks on his helmet, brainwashing him, but not before knocking Rick out of his own state. With Tony's armor being locked and his voice filters shut off by Rhodey, the Controller used him to attack another AIM base, one that was guarded by MODOC. They easily overpowered all resistance, but the Hulk, Rick, and Pepper smashed in. When Hulk smashed Iron Man's controller disk, the Controller took over Rick and ordered the Hulk to tear off his helmet. Iron Man woke up just in time to blast the Controller to release Rick. Finally, the sight of both Iron Man and Hulk approaching him made the Controller so afraid that he fainted.
The armor was later shown exploding in Tales of Suspense Part 1.
The Hulkbuster armor returned and was used to battle Iron Monger and Titanium Man in Heavy Mettle. He and War Machine were able to subdue Iron Monger and blast Titanium Man into another region of the planet.
Iron Man uses Extremis to bring his Hulkbuster Armor to him to use to subdue the Hulk. He first uses it to save the SHIELD Helicarrier then fights the Hulk, but not even the Hulkbuster combined Tony's Extremis power can stop him. Hulk rips off the arm servos and knocks it down.
The Hulkbuster Armor was designed for maximum strength and durability at the cost of reduced mobility, presumed to be a mix of the original Crimson Dynamo Armor specifications and the Iron Man suit. It is used as a modular unit for his standard armor, connecting itself within the Hulkbuster. Its capabilities are the following:
- Superhuman Strength: This armor was designed fight toe-to-toe with the Crimson Dynamo in combat. It has strength that allows it to push the Dynamo armor through several walls and its maximum strength is enough to hold off the Hulk.
- Enhanced Durability: Its durability is also impressive, it can take lasers, missiles, and anti-aircraft weapons with absolutely no effect on it. The armor can also withstand a pounding from an angry Hulk with minimal damage. It is a strong possibility that it could withstand the temperature of the sun just like the original Crimson Dynamo suit.
- Flight: It can hover and fly through the use of jet thrusters in the boots and a jet pack on the backside.
- Repulsor Gauntlets: Its gauntlets have the following:
- Repulsors: It has more powerful versions of the repulsors.
- Energy Absorption: He can directly absorb energy through his repulsor ports.
- Secondary Propulsion: It has propulsion jets inside its repulsor palms to use in flight.
- Force Field: It can form a force field around itself and others. The Hulkbuster armor has the strongest shields out of all the Iron Man armors.
- Unibeam: It has a more powerful version of the unibeam. One blast at point-blank range was able to completely destroy the Crimson Dynamo Armor.
- Rocket Launchers: It is equipped with rocket launchers in the waist.
- Gatling Guns: It is also equipped with shoulder-mounted gatling laser blasters.