
Marvel Studios removed one of its weirdest-looking villains ever from Captain America: Brave New World, and that may have been the right call. Alongside a focus on Harrison Ford's Red Hulk and Tim Blake Nelson's Leader, Anthony Mackie's Captain America went toe-to-toe with Serpent (aka the Serpent Society) in his first theatrical solo outing. The mercenary group was headed up by Giancarlo Esposito's Seth Voelker, aka Sidewinder, but Serpent almost had more members in their live-action debut.
Captain America: Brave New World - The Art of The Movie book finally hit shelves, and revealed concept art for a weird cyborg villain who was ultimately cut. WWE superstar Seth Rollins was expected to play Cobra, aka King Cobra, in Captain America 4, but was removed during reshoots, and it appears he was planned to have a cybernetic design that could have looked disgusting on the big screen.

Concept artist Keith Christensen commented on Cobra's twisted body design in the Captain America 4 artbook, explaining how they planned to "interpret the qualities of a cobra" with the cybernetics he was originally planned to have:
"We were thinking about how we could interpret the qualities of a cobra with the enhancements that he has in his body, because at that point, we were treating the Serpents as infused with technology--almost to the point of large portions of them being android or robotic or whatever."

He added how the design became "something super literal" and was imagined as if his body were that of a cobra shedding its skin:
"I went for something super literal, thinking of a cobra spreading his hood and thinking how his whole body could change to mimic that."
Scooper MyTimeToShineHello recently addressed Captain America 4's original cyborg Serpent Society plan, confirming that their upgrades were supposed to be made by Alden Ehrenreich's Zeke Stane from Disney+'s Ironheart.

While Cobra never made it into Captain America 4, his scenes were seemingly shot as WWE superstar Seth Rollins was expected to play the villain before reshoots replaced him with Giancarlo Esposito's Sidewinder.
Catch a peek at Rollins' final Cobra costume that was shot for Captain America 4.
A further design revealed that Cobra had another look where his body was completely covered, presumably hiding his gross cybernetics that would have been exposed when he rips this disguise off as the action begins.

While Captain America 4 originally planned to include Diamondback, King Cobra, and more, the only members of the Serpent Society (referred to in the MCU as Serpent) in the movie are Sidewinder and Copperhead.
Brave New World recently started streaming on Disney+ after its theatrical release in February and stars Anthony Mackie, Danny Ramirez, Harrison Ford, Tim Blake Nelson, Shira Haas, Carl Lumbly, and Xosha Roquemore.
Why Captain America 4 Had to Cut This Cyborg Villain
The Serpent Society didn't end up having cybernetics or superpowers in Captain America 4 and were instead portrayed as well-equipped, skilled mercenaries. In the art book, producer Nate Moore attributes the Serpent Society's change in direction to Brave New World's shift in tone:
"There were some ideas early on to see if we could ground them in a reality that didn’t feel as crazy as some of the stuff that was in publishing but still gave you the silhouettes, and some of those designs are really cool. But as we started to hone in on the one of the film and reall really wanted to lean into the more grounded world of a political thriller, we felt like even those attempts still felt too heightened for the start of the movie."
While fans will never know how King Cobra would have looked in live-action, his concept art looks somewhat disgusting and may be best left on the cutting room floor. After all, these cybernetic implants shifting across his body in snake-like fashion could have been a little too gross for a PG-13 audience.
Despite being among the confirmed villains for Captain America 4, Seth Rollins' MCU debut is, unfortunately, still yet to arrive. Perhaps whenever the Serpent Society happens to show back up, the WWE icon will return to get another go at King Cobra alongside Giancarlo Esposito's Sidewinder.