We (finally!) gained our flawless charms last night!
To gain these charms your guild must kill 19 of The Shadow Odyssey Raid bosses with out dying. Our final mob was Ykesha, and after several attempts, we killed him to get our flawless charms!
Feldon has a blog post of the Flawless Charms here, you can see the stats.
Grats to everyone in DA who worked hard to pull off these flawless kills!