|“||Nanomachines, son. They harden in response to physical trauma. You can't hurt me, Jack.||„|
|~ Armstrong, demonstrating his abilities to Raiden|
He is voiced by Alistair Duncan.
Sometime in 2016, Senator Armstrong delivered a speech to get his approval ratings up. His speech was his way of expressing his beliefs. Armstrong also had some involvement with the Desperado PMSC and its activities, to which his speech writer warned him that he'd appear before a grand jury had his connection to the group been revealed, although he himself believed that they won't do a thing in either case, as he believed that the people wouldn't care due to believing that money is the only thing that truly matters.
Recruiting Jetstream SamDuring all this, Armstrong was planning on recruiting a mercenary to help further his plans. After Jetstream Sam head to the top of the roof of World Marshal where Armstrong was waiting, Armstrong challenges Sam to a fight. While the two were fighting, Armstrong was offering Sam a job. Nearing the end, Sam managed to slice off one of Armstrong's arms, but Armstrong quickly retaliates by using his Nanomachines to turn his injury into a blade. He then process by stabbing Sam in his right shoulder, severely injuring Sam's entire right arm. After defeating Sam, Armstrong quickly attaching his severed hand back onto his arm, and accepted Jetstream Sam to the team, and eventually giving Sam a new robotic arm.
Direct involvement in Desperado activities
Two years later, Armstrong inspected a Desperado research lab in Mexico alongside with Desperado's leader; Sundowner, regarding that the transportation of children's brains in cyborg head casings before delivering them to World Marshal for the Sears Program was processing as planned. However, Armstrong also instructed them to shut down the facility, and move the child's brains to another facility as he had suspicion that someone was snooping around. One of the scientist asked Armstrong what to do with the other children that were attending the Sears Program. To which, Armstrong to him to kill them, as they had one where else to go, no one will miss them, and he claims that he's doing a public favor. He also plotted for Operation Tecumseh, which was a plan that would start a war with Pakistan under false pretenses while President Hamilton is visiting the country with Pakistani President Farooq Salam for a peace talk.
While Raiden was in the Pakistan base to stop Armstrong's plans, he spotted Blade Wolf injured, presumably defeated by Armstrong. Shortly after, Armstrong, along with his own Metal Gear, known as the Metal Gear EXCELSUS, climbed out of a crater. He revealed to Raiden that, since the fall of SOPs (Sons of the Patriots) and the Patriots, America was hit with a recession, which is the reason why he needed to orchestrate a false flag operation to ensure the war economy to put America back to work again. Although Armstrong was originally planning to assassinate the president, he instead, decided to have the American base framed for being killed by Pakistani extremists, feeling that would have accomplished the same plan in general. However, Raiden was planning to expose the truth of what happened, so to prevent that Armstrong confronted him with his Metal Gear.
After EXCELSUS was destroyed, Armstrong proceeded to fight Raiden. His nanomachine-infused body, which enabled Armstrong with superhuman-like strength and durability, completely overwhelmed Raiden, not even flinching once from the many hits the latter had landed on him. He even broke Raiden's sword, leaving Raiden to his mercy. During the battle, he explained that his motives of wanting to remake America. He believed that America was rotten to the core, and that he wanted to re-establish America as a world where people fight for their own reasons, instead of fighting for the government. Raiden then deduced that he wasn't merely a "greedy politician" as he initially thought, but stated that he was completely insane due to his reference to culling the weak and having the strong be free.However, just when Armstrong was about to kill Raiden, an injured Blade Wolf saved him by bringing to him Samuel Rodrigues' sword. Angered, Armstrong kicked Blade Wolf away, although not before Blade Wolf threw the sword to Raiden. Both Raiden and Armstrong continued to fight, until Raiden managed to stab Armstrong through the chest. Upon his defeat, Armstrong acknowledges Raiden as a true American, and expresses his respect for Raiden by informing him that he's "number 1." Raiden then finishes the former senator off by ripping out his nanomachine-laced pale heart and crushing it with his hand. Before he died, Armstrong commended Raiden as they were kindred spirits.
Armstrong's death, caused World Marshal's funding being crippled. But despite this, World Marshal itself still continued to exist, and his plan of re-orchestrating a new War on Terror managed to succeeded.
Armstrong is shown to be extremely nationalistic he shows this by expressing the desire to "reclaim the American dream" by instigating another American revolution after Liquid Ocelot's insurrection and the Patriots' actions that weakened America. His intense patriotism was fully demonstrated while he was fighting Raiden, by declaring that if Raiden was not for the United States and his goals, he was effectively against it. He also told Raiden to feel the wrath of the USA, and saying that Uncle Sam desired Raiden's death.
PowersBeing enhanced with Nanomachines, Steven Armstrong's main ability is allowing him to absorb and store energy. This grants him superhuman strength, and durability. He can use his Nanomachines to hardened his body in response to physical injuries. These Nanomachines also allows him to generate fireballs, create fiery shockwaves, and heal his injuries. He's also shown that he can levitate and throw vehicles as he's absorbing their energy. If he somehow has his limbs severed, he easily reattach the limb with no effort. All of these abilities are controlled by his artificial heart.
- The moment Armstrong is about to absorb his nanomachines he does a Sumo pose. Steven also performs a variety of wrestling moves during his fight with Raiden.
Metal Gear Solid: Portable Ops
Metal Gear Solid: Peace Walker
Metal Gear Solid V: Ground Zeroes
Metal Gear Solid V: The Phantom Pain
Metal Gear 2: Solid Snake
Metal Gear Solid
Metal Gear Solid 2: Sons of the Liberty
Metal Gear Solid 4: Guns of the Patriots
Metal Gear Rising: Revengeance