Invasion of Castle Zemo
The Invaders were given the task of infiltrating Castle Zemo to put an end to the experiments being carried out by HYDRA scientist Arnim Zola. Captain America was sent in first to shut down the castle's long-range air defenses and allow the Invaders safe passage. Rogers was successful in destroying the three 88-millimeter automated cannons, but a Pulse Cannon was then unveiled. Rogers attempted to disarm the gun by destroying its radar dish, but was ambushed by Baron Wolfgang von Strucker and his henchmen. Rogers fought his way through them and destroyed the dish, but the Invaders' plane was his by one of the cannon’s stray blasts, forcing them to parachute out. Dum Dum Dugan, Bucky Barnes and James Montgomery Falsworth landed near the castle and were captured, while Jim Morita, Gabe Jones and Jacques Dernier landed far enough away to avoid being caught. Strucker forced himself and Rogers off of the tower and incapacitated Rogers in mid-air with his Satan Claw as the plane crashed into the tower. Rogers was then taken in by Iron Cross.
- "Has there been any word from the Invaders?"
"They all bailed out before the crash. Dernier, Gabriel and Morita have set up some small artillery on a nearby hillside.. They said Bucky, Falsworth and Dugan bailed out over the castle."
"Then Madame Hydra's got them. They're probably nearby."
- ―Captain America and Peggy Carter[src]
Captain America was taken before Arnim Zola and Madame Hydra, where he learned that they planned to use samples of his blood to complete Project Master Man by duplicating the Super Soldier Serum and creating an army of superhuman soldiers for HYDRA. Rogers later escaped the cell he was placed in and found a radio, contacting Peggy Carter. She informed him the Bucky Barnes, James Montgomery Falsworth and Dum Dum Dugan had been captured and Jacques Dernier, Gabe Jones and Jim Morita had set up artillery on a nearby hillside. Rogers advised her to inform Morita to keep the artillery handy.
Rogers recovered his shield and gear belt. He found and rescued Barnes, who informed him that HYDRA had been torturing and starving prisoners from the United States of America, the United Kingdom, Russia and France among others. He informed Rogers of a railway tunnel they could use to smuggle the prisoners out and gave him a miniaturized short-range radio receiver that Howard Stark had developed to keep in touch with the Invaders. Rogers dealt with the snipers while Barnes freed the prisoners. Using a cannon, Rogers cleared the area around the track of HYDRA troops, allowing the train carrying the prisoners to get through in one piece. He then had Morita, Jones and Dernier blow up the bridge to prevent HYDRA from pursuing the train.
Rogers progressed further into the castle in search of Dugan and Falsworth, where he found HYDRA's scientists being slaughtered by the escaped Screamers, hideous and bloodthirsty mutated troops. Madame Hydra announced her intention to leave with Falsworth and leave Dugan behind as bait for the creatures. Roger located and freed Dugan, at which point they made plans for Rogers to rescue Falsworth and Dugan to destroy the Pulse Cannon. They were then attacked by Screamers, forcing Rogers to defeat them while Dugan escaped.
Rogers found Falsworth being led to another part of the castle, and she fled inside when Dugan fired at her. Rogers pursued her while Dugan made his way to the Pulse Cannon. Rogers fought Madame Hydra in the East Wing of the castle, scarring her face when he set off a bomb by deflecting her bullets, causing her to flee in a helicopter. Dugan destroyed the Pulse Cannon, after which the Red Skull arrived with the Tesseract. Rogers took a train to the northern part of the castle, destroying the factory and locating Schmidt and Zola, who were guarded by Iron Cross. Zola unveiled the perfected Super Soldier Serum, which Rogers then destroyed with his shield. Schmidt ordered Gruler to kill Rogers while he used the Tesseract to wake the Sleeper, a massive robot of unknown origin. Rogers defeated Gruler and attempted to pursue Schmidt, but was knocked into the depths of the mountain by the Sleeper.
Rogers awoke and discovered that Falsworth was in the northern chapel, alerting Barnes and Dugan who insisted they rendezvous with him. Rogers reached the chapel and located Falsworth, whom Zola was intent on turning into a super soldier and the perfect assassin. Rogers battled and destroyed a Zola Bot, freeing Falsworth as Barnes and Dugan arrived.
Destroying the Sleeper
- "Listen to me. None of us are special. If we win, that'll be why, because Zola and Skull think they're some master race, and we know they're not. We know no man is more valuable than any other. We know it'll take all of us to stop this evil from spreading. All of us standing together, doing our part. I'm best equipped to go down there and see if there's anything I can do to stop it. To find out what I can and relay it to you. But the truth is it's probably more than I can handle. Which means it's up to you to stop it for good, with mortars or airstrikes or whatever it takes. We either win together...or we die together."
"We'll carry out our duty, Captain. Have no fear of that."
"Give 'em a boot in the head from me."
"See you soon."
"When the evacuation plane comes, you be there to meet them. With or without me."
- ―Captain America, James Montgomery Falsworth, Dum Dum Dugan and Bucky Barnes[src]
With the Invaders rescued, Captain America insisted that they needed to destroy the Sleeper. Rogers set out a plan for him to attack the Sleeper from the ground level and search for its weaknesses while the others came at it with mortars and airstrikes. He ordered them to be on the evacuation plane, with or without him.
Rogers made his way to the courtyard, where the Sleeper rose from beneath the ground. Fighting his way through the Zola Bots, Rogers distracted the Sleeper while Bucky Barnes, Dum Dum Dugan and James Montgomery Falsworth attacked it from the ground and Jim Morita, Gabe Jones and Jacques Dernier did the same from the sky. Through an airstrike and Rogers' shield, they took out both of its eyes, preventing it from shooting down the planes. Rogers noticed cables in its neck, which he had Dugan shoot at to expose them before destroying them with his shield, decapitating the behemoth and destroying it once and for all. The ensuing explosion destroyed the castle, which Rogers barely escaped from. Rogers and the Invaders then escorted HYDRA's former prisoners to safety.