In 2010, the Roxxon Corporation oil tanker Norco spilled a million gallons of crude oil off the coast of Pensacola. Matthew Ellis used his political influence to ensure that the Roxxon executives avoided being judged or imprisoned for the event.
Acquisition of the Norco
Aldrich Killian acquired the Norco as a base of operations. He decided to use it as an excuse to kill President Matthew Ellis and make it seem as a Mandarin terrorist action for political reasons due to Ellis' role in the aftermath of the oil slick.
Arrival of President Ellis
Aldrich Killian arrived at the Norco and checked on Pepper Potts when she was brought to the ship after being injected with Extremis. He revealed that Potts was taken captive not just to motivate Tony Stark into stabilizing Extremis, but actually as Killian's personal "trophy".
Killian greeted President Matthew Ellis as he arrived while inside the Iron Patriot Armor, who recognized the ship as the Roxxon Norco. Killian explained his motives, as he did not want to negotiate for the president's life; Killian intended to assassinate Ellis masquerading as a Mandarin terrorist attack in order to let Vice President Rodriguez, secretly in league with him, to become the new president.
Arrival of the Iron Legion
Tony Stark and James Rhodes were able to board the Norco, but outnumbered as the tanker was guarded by a large squad of Extremis Soldiers. Rhodes located President Matthew Ellis, tied inside Rhodes' Iron Patriot Armor waiting for his public execution.
Stark and Rhodes were spotted by the soldiers, and forced to take cover, while starting to be surrounded by the soldiers. Stark grew confident as a humming noise was heard approaching, and Rhodes asked if it was what he believed it was. A whole legion of Iron Man Armors surrounded the Norco, providing much-needed backup for them.
Stark ordered J.A.R.V.I.S. to target the soldiers due to their unique heat signatures, and neutralize them with the maximum prejudice. The armors started battling the Extremis soldiers, gaining the upper hand though some of them were destroyed during the fight around the ship. Stark also defined some of the battle strategy for the armors, such as ordering the Mark XXXVIII to stabilize structure of the oil tanker.
Stark donned one of his armors to battle himself, but did not let Rhodes wear one as they were explicitly coded for Stark. An armor controlled by J.A.R.V.I.S. carried Rhodes, but they were attacked by a soldier and forced to jump to one of the footbridges. A pair of Extremis soldiers attacked Rhodes, but Stark's armors easily defeated them before they could harm him.
Stark went on to rescue Pepper Potts, still held prisoner inside the tanker, but she was hit by one of the explosions and trapped under a large amount of debris. Killian then attacked Stark and disabled the Arc Reactor of the armor using his advanced Extremis Soldiers abilities, and taunted Stark due to his inability to defeat Killian in front of Potts. However, Stark waited until the last moment and cut off Killian's arm. The severed limb started to melt the Norco's floor due to its high temperature, causing Potts to fall through the open hull and leaving her stuck on a nearby gantry.
James Rhodes went to save President Matthew Ellis and defeated a pair of Extremis Soldiers, tricking them into falling from the container into an explosion as they ambushed him. Rhodes liberated the president, and recovered his armor. As Iron Patriot, Rhodes rescued Ellis and took him away from the ship.
Meanwhile, Stark rushed to save Potts as the platform she was on moved to the other side of the tanker. He tried to convince Potts to let go as he would catch her and pull her to safety, but the debris moved and Potts fell to her seeming death, leaving Stark devastated. Killian reappeared, having regrown his arm, and taunted Stark again for letting Potts die. Stark angrily confronted Killian, using different armors that were destroyed in their fight, and avoiding a fatal blow in a scenario proposed by Killian to the rooftop in Bern where they never met.
After they had battled throughout the tanker, Stark waited as the Mark XLII armor approached, but it crashed against an obstacle and disassembled into pieces. Killian prepared to kill Stark and taunted him for what he thought would be the last time. However, Stark, buying some time, declared that he may not have deserved Potts, but there was no need to improve her, as she was already perfect. Stark ordered the Mark XLII to attach itself onto Killian, and asked J.A.R.V.I.S. to trigger the self-destruction of the armor to kill him.
Aldrich Killian barely survived the explosion, and confronted Tony Stark at the bottom of the tanker, claiming that he was the Mandarin, but was interrupted by Pepper Potts, who had also survived her fall. One of the armors approached, intending to attack Potts due to her Extremis heat signature, but she angrily destroyed it with a single punch, tearing off the repulsor gauntlet. Potts then used it to detonate a missile that she launched at Killian, finally killing him.
Stark and Potts, relieved by the end of the battle, discussed how they would deal with the aftermath, as Potts finally came to understand Stark's obsession with his armors. She was worried about hurting Stark with her Extremis powers, so he promised to help Potts without anymore distractions. Stark then ordered J.A.R.V.I.S. to destroy all his remaining armors with the Clean Slate Protocol, as he and Potts watched the fireworks display above the tanker.