The second iteration of 2v8 is now LIVE - find out more information here: https://forums.bhvr.com/dead-by-daylight/kb/articles/480-2v8-developer-update

Rework Memento Mori

After you hang 4 survivors. When 4 survivors are taken down, after 5 seconds. All other 3 survivors (not the one you took down) take effect and may be killed. A lying survivor gets no effect.

 As soon as that one is killed, the effect disappears.