[3][4] Barney Barton debuted in The Avengers #64 (May 1969), created by writer Roy Thomas and artist Gene Colan.

Later, when Clint was severely injured at the hands of the Swordsman for discovering his embezzlement scheme, Barney condemned his brother for not remaining loyal to his mentor.

The next morning, Barney stood at the bus depot, waiting and hoping his brother would change his mind.

With his bodyguards slain, Barney went to the Avengers (whose ranks included his brother using the identity of Goliath) to help stop the supervillain.

[18][19] After the funeral, Clint received a letter from FBI agent Allan Scofield revealing Barney's double life.

Egghead discovered that Barney was still displaying faint vital signs and placed him in a healing chamber.

[21] Later, Egghead was inadvertently killed by Hawkeye in a battle with the Avengers, leaving Barney suspended and forgotten in the healing chamber.

[21][23] Barney and his new "benefactor" enlisted Hawkeye's former mentor Trick Shot (whose cancer had returned) to train him to be as proficient with a bow and arrow as his brother.

Before teleporting away, Zemo transferred Barney's criminal funds over to the "victor" Hawkeye, then taunted the hero for turning his brother against him.

In custody, Barney agreed to a bone marrow transplant to save his brother's sight, but only so he could battle Hawkeye again in the future.

[29] After being arrested, Barney and the rest of the villains (save for Superia and Gorgon) are offered reduced sentences in exchange for signing on with the Thunderbolts program.

[37] Barney Barton is a highly trained former FBI agent and is a proficient marksman, exceptional athlete and skilled hand-to-hand combatant with incredible reflexes.

"[40] Jordan Iacobucci of Screen Rant wrote, "If the MCU intends on adapting the Dark Avengers storyline with its Thunderbolts, Barney Barton is an excellent choice, as his addition could both enliven Clint Barton's character arc, as well as inform a potential second season of Hawkeye, which is rumored to be in development.

The character is one major piece of Clint's story yet to be adapted for the MCU, who should reunite with his brother before Jeremy Renner's inevitable exit from the franchise.