As an aside, it does lead to think a) how much would a chaos-worshipping Rowboat Gorillaman be able to achieve and b) man, you’d thik rhat with Perty’s siege expertise that IW would be Ultramarines’ level of competent and at the forefront.
They thread the needle of taking seriously the premise of “what would a Khorne-worshipping civilization that didn’t eat itself up look like in the long run” and keeping to the satire of the setting (better than some BL novels LOL)