I've been seeing alot of questionable groups in other worlds that even the creators are getting sick of seeing. Like for example: A bad group like a N*zi based group would create an instance in my own world that I created, I want the ability to blacklist their group from creating instances in my world. I think this would serve well for world creators to filter out bad groups that are using their worlds but whatever purpose they are using it for, especially for worlds that are typically used by toxic RP based groups.