To me was the exotic hand cannon First Curse. It was impossible without the help of my friends..., heck, Thorn bounty was easy back in the day compared to this one (and i did that bounty with a titan). What's your impossible to get exotic? Edit: lots of people having trouble with some especific exotics, most of them with Thorn and the Chaperone (that last one did surprised me, for me it wasn't that hard). Also, many people argue that some exotics, like Necrochasm is really hard to get, not like thorn or the curse that you get it by mere effort, no, the problem here is RNGEEZUZ that has zero mercy on your poor souls...