Hoppered the Gauntlet
Hoppered the Gauntlet is a man with severely degenerated legs, which he covers with a specialized suit of armor that functions almost like a exoskeleton. He gets around by using his powerful arms to propel himself, and can reach impressive speeds by using his shield as a launching mechanism.
He's driven by a personal vendetta against Vash, initially motivated by the death of a mute and blind woman who'd isolated herself from the world—she was killed during the destruction of July. His obsession with revenge consumes most of his character arc, though the anime adaptation strips this backstory entirely, instead portraying him as simply wanting to make Vash suffer for its own sake.
Things change dramatically during their final confrontation. When Hoppered witnesses Vash's memories of July, he experiences a sudden realization that he's been chasing the wrong goal all along. He abandons his vendetta and turns against the Guns instead. The shift doesn't save him—he's killed when he throws himself onto an energy core and it explodes, taking him with it.
Content compiled by AnimeList.moe from publicly available sources.