The exotic quest for the Xenophage is the single most bugged thing I've experienced in the game. I've completed one of the LS puzzles and the rest just don't work, I've been trying most days for 2 weeks now and it's legitimately upsetting. Worst thing is, there's fireteams and activities I'm literally getting kicked from for not having certain weapons, and Bungie can't be bothered to fix things that have been in game for ages...