By reaching into a victim’s mind, a mage can diminish the target’s perceptions and make it less likely that he will notice anything that doesn’t already hold his focus.
Each success on the roll reduces all of the target’s reflexive perception dice pools (generally Wits + Composure) by one for the duration of the spell. Though the spell won’t impede a determined search, the target is less likely to notice anything peripheral to her attention or react quickly to surprises.
Guardians of the Veil Rote: Dimmed Sight
Every spy and secret agent wants the power to affect those around her so that she may pass unnoticed. The Guardians of the Veil have it, and they use it to great effect. Although this rote becomes unwieldy or ineffective if there are crowds about, Dimmed Sight is quite good at getting the Guardian through slow bank lobbies and past bored security guards.