Trailers for Avengers: Infinity War, with Anthony Russo giving a not-so-subtle hint where the replacement came from. "I think that, you know, we catch back up with him after he's been there for a while," he observed. "and if there's an influence on his arm, it may perhaps have to do with that country that he's been spending time in."

The cyborg arm was never really explored in either Avengers: Infinity War or Avengers: Endgame - there was too much going on - but trailers for Falcon & Winter Soldier have confirmed Bucky's now sporting a Vibranium arm. One TV spot saw Bucky confirm as much, as he strapped the arm on to his shoulder, revealing the Wakandan tech that makes it work.

Related: The MCU Just Retconned Spider-Man 2's Bucky Barnes Reveal

Vibranium is a rare metal with very special properties, which means this is no ordinary replacement arm; it's an enhancement that helps make Bucky a true super-soldier. Here's everything this arm will be - and could be - capable of.

Super Strength

A poster for Bucky Barnes in The Falcon and the Winter Soldier

Hydraulics in Bucky's old Hydra arm always afforded him a degree of superhuman strength, as he demonstrated with some particularly chilling piledriver punches; only superhumans like Spider-Man were able to catch the Winter Soldier's punches, and even Steve Rogers struggled to hold that arm back. It's reasonable to assume the Wakandan version will be no different, and indeed Bucky may well be stronger than ever before.

Kinetic Energy Absorption

Sebastian Stan as Bucky with Captain America Shield

Vibranium's most remarkable property is its ability to absorb kinetic energy. This characteristic was first demonstrated in Captain America's shield too - although the ts will probably be weaknesses. Once Bucky has gotten used to the arm, he should be able to integrate it into his general combat style, using it to boost his athleticism. He should be able to vault higher and more effectively than ever before, and if he uses it to block a punch then an attacker is likely to break their wrist.

Kinetic Energy Projection

Black Panther MCU Suit

But here's where things get really interesting; Bucky's cyborg arm was likely created by Shuri, Wakanda's greatest scientist. As seen in the Winter Soldier doesn't need a gun or throwing weapon to get to enemies at a distance.

Related: Falcon & The Winter Soldier Shows Bucky's Wakanda Redemption Isn't Complete

Vibranium Can Be Deactivated

Wakanda Great Mound

But Black Panther also set up a weakness for the Winter Soldier, because the film revealed it's possible to generate some sort of electromagnetic field that renders Vibranium inert. It's unclear whether this particular Wakandan secret has been shared with the world during the Blip, but if it has then some of Bucky's enemies may be able to figure out a way to weaken him considerably if they realize what his new arm is made of. Bucky may not want to his new abilities too widely in Falcon & Winter Soldier.

More: Why Bucky Ages Differently Than Captain America

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