Reward 1 guaranteed skeleton key a week after doing the nightfall, and you can do it once per character! This will make nightfalls still useful even at max light or maybe give a guaranteed skeleton key after doing the first iron lord weekly bounties (Please bump to show bungie) Edit 1: We are on the trending page! Cozmo is sure to see the post soon :D keep bumping the post Edit 2: I just thought of another idea, what it the vanguard streak would increase skeleton key chances?