Veil

A veil is a magical form of concealment which renders the affected either invisible or otherwise unnoticed by most of the magically unaware.

Description
Veils can range from simple feelings of aversion to looking in a direction, to a lack of conscious recognition of someone's presence, to a complete state of invisibility and denial of the existence of the physical space in which the veil stands.

Veils can be seen through with the Sight and perhaps some varieties of sentient magical creatures.

For the creation of good veils the creator needs a good control of magic, and to be calm and still.

Being under a veil also always reduces the veiled person's ability to see or perceive the world outside the veil.

Obscurata is the spell word for a simple veil.

Blood Rites
In Blood Rites, Harry Dresden states that Mavra is very talented in creating powerful veils.

Small Favor
In Small Favor, Molly Carpenter is noted to be especially talented with veils due to her better fine control.

Changes
In Changes, Dresden has gotten better at them after teaching Molly. A simple veil is no longer beyond him. He uses one when when vampires approach his office building.

Cold Days
In Cold Days, Dresden used a veil: "Obscurata", in his fight with Fix on the top of the hill on Demonreach.