Vanishing Facial Copy Technique

The user applies their hand to a target's face, allowing them to take the face and use it as their own. Because it's the actual face that they're using and not a disguise, the user runs no risk of being discovered due to imperfections or minor flaws. The bodies of those whose faces have been stolen are, as a consequence, quite ghastly to look upon. After Orochimaru uses this technique to take the face of a Kusagakure-nin, his voice changes as well, though it's not clear if that's part of this technique. As he takes damage in combat, the stolen face gradually wrinkles before finally tearing away, revealing Orochimaru's face underneath. Orochimaru can also remove the face himself when he no longer needs it.

Trivia

 * This technique is reminiscent of the Noppera-bō, a ghost from Japanese folklore that resembles a human with no face.