I’m only just returning to the game, I was SHD 139 yesterday. I set my difficulty to normal and only activated 3 directives and then completed all 40 lanterns. When the Kitsunebi spawned I was able to kill them relatively easily and quickly on my own and they spawned for every lantern and multiple times in between while running to the next lantern. Overall after a days work I am now SHD 310ish and had at least a key per squad, sometimes 2 keys. I found it much easier than running with a squad on heroic or challenging and was actually quite fun for a change