User blog comment:Rafe Adler/"Family Feud" Discussion/@comment-28192538-20170224073809/@comment-1031724-20170301182310

Lucifer will die only when the writers are ones who believe in old-fashioned endings, which the series stopped playing straight after Abaddon.

Crowley will die when either it's clear Crowley isn't fun to have around anymore (which could be due to the show going on for way too long!), or when they decide they know no bounds in killing fan favorites anymore.

Show will end when the sun sets in the east and rises in the west, and when Frozen merchandise disappears.