In BLOPS2 I spent way too long making a Zeon emblem, and I didn't feel like putting the work in again, so I found one that I found adequate and am using that because I'm lazy. There are a few things about it that bother me, so I may end up making my own eventually anyway, but it's what I'm using for the time being.
EDIT: I've since edited it, getting rid of bad layer connections and smoothed out uneven lines and whatnot. Now it's perfect.
Found a badass Slaanesh emblem too that I may use in the future, but not yet.