Nope, it's 4.

Syntax: STARCHANT NUMEN
Power: 4 (Pool of Stars)
By surrounding yourself with a numen of light, any damage dealt to you will be
halved.

Edit: And i can do them without numen too, it's just easier that way

And Numen is a bit random too. It works from 30sec to 1 minute.
But mostly it wears off after 40 sec.
So 1 power for 10 seconds of half damage