Xan Krieger said:
Cadia is technically not a Death World. Its a Primus Class Fortress World and Naval dockyard too. But you're right. Chaos Marines are practically an indigenous species.
And basically every single world in the Eye of Terror is a literal hell planet, including a personal favorite that isn't a planet at all but a massive obese naked man curled up into a ball.
See?
http://wh40k.lexicanum.com/wiki/Oliensis