Captain America – John Walker

In the past, John Walker was a confident and charming three-time Medal of Honor winner. He was also a soldier, trained in advanced hand-to-hand combat, firearm improvisation and modern army combatives, and carries a US Army pistol that is holstered on his utility belt.

He was the first replacement for Captain America since the end of World War II and he quickly became popular with fans, but he had a dark side. Walker was prone to anger, such as when he shoved a German man for spitting in his face or when he ruined an attempt by Wilson and Barnes to negotiate with Morgenthau. He also acted with arrogance, treating Wilson and Barnes as Rogers’ “wingmen” rather than as people he could learn from.

After losing his parents in the Blip, Walker began to lose control of himself. He secretly took the Super-Soldier Serum from S.H.I.E.L.D and gained super-strength and a bloodied Cap Vibranium shield. His dark side manifested as he went berserk and murdered one of the Flag Smashers in front of civilians and Sam and Bucky.

Despite his instability, Walker continued to fight as the U.S. Agent, filling in for the core Avengers and the West Coast Avengers on occasion. He also served as a member of the government-backed team, The Invaders, and even the Canadian super-team Omega Flight. During his time on The Invaders, he clashed with Wilson and Barnes and was almost tricked into turning against them by the doppelgänger Dell Rusk (actually the Red Skull in disguise). Walker also took part in an attack on the White House by the Dora Milaje.