I guess we (I said we coz I want them too with no luck eighter) farm it when it becomes a Nightfall. It apears that the strike specific item drops on HUGELY increased rates during the nightfall. I got the Threads Upon Stars 2 out of 3 runs during this weeks Psions and other ppl confirm the same results. What Iam trying to say is the the higher the difficulty of the strike is, the higher the chances for the drop is and it goes like this: [b]From lowest chance to highest[/b] lvl 16 strike from map > legacy strike > Vanguard strike > Heroic strike > special strikes for quests ( SABER for Sleeper Simulant, Shield Bros for Chapperone, Sunless Cell for the exotic sword) > and last is the Nightfall