I opened a weapon box in the Halloween Event, after completion, chose my dual pistols and it gave me the Memento Mori feat for collecting two emblems.
This feat is bugged, it popped when I collected the Mr Boo emblem and the Klarion boots style. I have no other emblems from that year on that character.
Someone else reported the same issue before https://forums.daybreakgames.com/dc...nto-mori-granted-upon-weapon-box-open.325036/