When I think about Imperial Guard, I think of the heroism of ordinary soldiers ordered to stop the unstoppable, and relying on, above all else, honest human courage. This is the song that makes me think of the Imperial Guard:
Word Bearers Procession Music. View: http://www.youtube.com/watch?v=w3WXfiB7OeY Also, Orky Song: View: http://www.youtube.com/watch?v=reOLeLX0Q9U
This sounds like a man waiting in front of an occupied toilet trying to keep from shitting himself, no offense. Props on Heidevolk though.
Here, a better procession music for Chaos if i do say so myself: View: http://www.youtube.com/watch?v=AFqQPH25-PQ
Excellent suggestions found here. I found theme to be quite wicked, and suitable for Tzeentch And this one for Slaanesh. I think it captures their decent to madness really well.