[quote=The Irish Tree]
Pfft. You think you need FLAMES to fight against flesh? All you need is to fight heresy with a brand of heresy that is okay with the Emperor. By that I mean you call in the Grey Knights.Or the Tau. Pretty sure the Emprah would be fine with the Tau.
[/quote]

Calling the Grey knights is basically just telling them to kill everything! It would be cheaper, faster, and more entertaining to just call down an exterminatus, But there are CIVIES down here! We can't just nuke 'em from orbit!