The Hellbrute is what we used to call a chaos dreadnought. It's a weird sculpt, more organic beast than machine, with a stubby little multi-melta and funny stumpy feet. I only made two conversions: the gun was lengthened with spare bits from the mephitic blighthauler (where do they get these names?) and the head was replaced with a suitably disgusting and eel-like tongue.
I originally painted it an odd light purple, but used a nasty raw flesh colour this time around, which was basecoated in crimson and worked up with flesh tones and bleached bone. I gave the most raised areas a glaze of yellow, for added unwholesomeness.
Life for a Hellbrute can be a lonely business, so I've made him a little friend, in the form of a decaying human torso with spider legs and a screaming mouth. I'm sure they'll get on fine.
Here's a back view, showing the Hellbrute's charming metal spine and gills.
Lovely! I really ought to paint up the marines, too. It's a shame that 40k doesn't have rules like the old Warhammer Path To Glory rules, where you had a handful of loonies wandering the wasteland and growing extra limbs. Perhaps they'll bring some out one day.