Dark mechanicus Genebrute 3
Genetic engineering allowed the Dark Mechanicus to vat grow a number of hulking monstrosities codified as Genebrutes for use in the Stygian Wars. Primarily used as shock assault troops and fueled by chemical induced rage that made them impervious to pain these massively strong creatures would hack apart all who opposed them with massive axes and their own surgically attached weaponry. Imperial command believes the "Charonite" Ogryns of the heresy era were the inspiration and original blueprint for these creatures. Other Imperial scholars point to genetic engineering done for the Iron Warriors Legion by the mechanicum particularly the case of the Schadenhold on Dantioch (see file 995.77-1) as the inspiration. Whatever the orgins, Genebrutes became a feared force to deal with throughout the Stygian Wars.
For game purposes I run the above model as a spawn with the mark of nurgle.