I haven't played a Duke Nukem game for about ten years, so I'm not sure how powerful he potentially is. But I'm not about to just say Krauser simply due to his bladed arm (and I've played buttloads of RE4, thank you). He was defeated twice in spite of it, and by people who's abilities are presumably at olympic level, maybe a bit higher, but not beyond humanly possible. But you know, put any of us against Krauser, and we'd be skewered endlessly, but I'd assume the same would apply if we were against Duke.