nearly a year of what Bucky dryly referred to as “Hydra and Seek” – where he torched Hydra outposts and Steve and Sam tried to pin him down and forcibly drag him into a group hug.
( . . . )
“Is that a ‘sthetic?” the boy asked, darting forward to grab it. Bucky stiffened. “Whoa, cool. Is it bionic? Mine’s 3-D printed.“

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Because Toothless had prosthetics, and Stark has prosthetics, and Bucky has prosthetics, и современные технологии позволяют именно «распечатать на принтере» еще одну руку (хотя это ни в коем случае не повод избавляться от настоящих).