This is an awesome concept bungie has done by putting gear you can only obtain by completing certain strikes, which i assume are nightfall tier only. If anyone knows if they can be obtained any other way comment and let me know. But to anyone reading this and is confused as hell about what a Darkblade Helm is the link to my video showing it and its perks is linked below. So far from my knowledge of running the strikes and different activities yesterday, it can only be obtained at the end of the Sunless Cell of the boss after you kill him. Recommended light you should have is anything 280 or above in my opinion. Im going to get back to it now to search for any crazy gear or exotics is the wild!! Nightfall Gear Darkblade Helm!!!! https://www.youtube.com/watch?v=KBo7Rp3y_yI