Warns of any approaching enemies (possible)
- "'Cave inimicum,' Hermione finished with a skyward flourish."
- —The last of the security enchantments being cast.[src]
Cave Inimicum is a Latin phrase which translates to "beware of the enemy".
- Harry Potter and the Deathly Hallows (First appearance)
Behind the scenes
- Whilst the true effect of this spell is unclear it is possible that it serves as some sort of early warning system for approaching enemies, similar to the Intruder Charm.