I began building with the head. It come out nicely and quite easily. The diamond teeth were a must, as well as the rotor on his helmet. I also wanted the eyebrows be adjustable to show different moods. I looked at Paul Kidby's art for inspiration, but there's less similarities than on Colon or Ridcully, for example. I had quite a clear image of Detritus on my head.
The scale was also interesting. As Detritus is a bit hunched, he's shorter than Carrot, but naturally much wider and larger. I haven't built this big SYSTEM characters before. But it wasn't that hard, after all. Poseable legs are the big difference here. They have those odd clickety KK2/Exo-force joints on the hip, click joints on the knees and ball joints on the ankles; plus additional pin-hole-to-studs hinges on the lower ankle. These help to balance the figure; that was rather challenging, especially with his siege crossbow The Piecemaker, which weights rather much.
Watch sergeants traditionally wear a Roman-esque muscular breastplates. I had already build one for Colon. There are some similarities, like the abs (boat stud, great piece all over again) and the inner structure, but the pecs are more dominant and hinged. The badge is almost hidden behind Detritus's impressive lower jaw. Otherwise the uniform follows the basic Watch uniform, with some leather flaps, bits of chain main, short trousers and open-toe boots, but he doesn't really wear shirt under the armor. I felt he didn't needed, as his skin is rock and he prefers to be cool, if you know what I mean (silicon brain).