User blog comment:Vivaporius/AT Idea: Imperial Civil War/@comment-3258762-20120408184922/@comment-2253300-20120408194430

My personal recommendation is that you shouldn't involve Loyalist Primarchs in this. They're too powerful. They're game changers, and their involvment inevitably overshadows every other heroes contributions in a conflict. Besides, we don't know what happened to most of them, and Guilliman is unavailable (I have looked at the science regarding his condition, and the odds of recovery are pretty much non-existant).