If going for Butcher's Crown (question)

[Victor]

Hello Helena ^^. First, you do not need to be the player that lands the killing blow; you can just be in the party that kills the claimed mob. Second, the mob does NOT need to yield XP. This is based off my own experience of getting the “100,000 enemies defeated!” notification by killing mobs within the Shposhae in which none of the monsters yielded any XP. Hope this helps!

Thank you for the confirmation. I spent the entirety of November in Shposhae killing ghosts and although I haven't hit 100k yet, I know I'm very close.