Though this isn't a personal experience, I went to my friend's house and watched him, his older brother, and another friend of ours carry him in the Nightfall. After several minutes, they finally defeated the Nexus Mind. When the rewards came up, my friend got Dragon's Breath! When this popped up, I heard my other friend's muffled sigh of jealousy and disappointment as he got a Legendary tier Scout Rifle, which he dismantled soon later.