So, I might be able to aquire a "starting death guard" force, in addition to this I already have some older death guard models and my old force of plague zombies from my ancient lost and the damned army. I also have tons of chaos stuff I could add in. However I have some questions... If I take CSM in a separate detachment and choose he mark of nurgle what does that do for me exactly? There are no special things going on with nurgle in the CSM codex, it just says death guard are different go see death guard codex. So what benefits do CSM get with the mark of nurgle? Just the nurgle keyword? Can someone explain what you get with the mark, how do you soup with CSM? I am not looking for a full death guard, more for a nurgle centric/themed army with an emphasis on death guard. Basically a mainly death guard with some CSM nurgle marked backup. Can someone explain some of the ways I can achieve this and how the two would interact.