Legendary engrams turning into rares.... On top of multiple times getting an exotic drop and turning around and getting the same exact drop within the same day. But one of the most frustrating was back when everyone had to farm like hell for material. I was dead tired from playing all night and then farming material for upgrading my new ice breaker and new raid gear before I went to sleep. I made my way back to the tower after farming 200+ spinmetal and 200+ helium and in a sleepy daze, I somehow managed to dismantle NOT ONLY the spinmetal, but also the helium. Talk about frustrating!,