xfactor
- Unknown element
- Hard-to-define influence
- Mystery quality ... or what 18- and 55-Across and 3- and 32-Down have?
- Je ne sais quoi
- Mystery quality ... or wh
- Special quality that's needed by female member of cast
- Noteworthy special quality
- It's fine by retiring luvvie
- Hard-to-define quality
- Unpredictable element