This technique is performed with the "cursed" kekkei genkai of the Yuki clan. Haku creates several large mirrors out of ice, which he surrounds a target with. By entering one of these mirrors, Haku's reflection will appear in all of them. Haku can travel between these mirrors near-instantaneously, giving the appearance that he occupies all of them simultaneously. As such, any attacks he makes from these mirrors - usually rapid volleys of thrown senbon - can overwhelm opponents, seemingly coming from every mirror at once. Using the technique requires a great deal of chakra from Haku, meaning he cannot use it indefinitely. In the anime, if the mirror the user is in is broken, they can leap out of one of the fragments and continue their attack or move to another mirror.
Although Haku moves between the mirrors extremely quickly, to the point that Rin no Sho describes it as light speed, it is still possible to track him: Sasuke Uchiha, with his undeveloped Sharingan, becomes able to follow his movements, and with enough time could even attack Haku; Naruto Uzumaki, after entering an initial jinchūriki form, is able to dodge and then catch Haku. Similarly, although the mirrors are quite resilient, notably not melting against fire, Naruto's jinchūriki form is strong enough to shatter one. The mirrors will also shatter if Haku stops maintaining them.
These exceptions aside, the Demonic Mirroring Ice Crystals is still a formidable technique. Most victims will be unable to do anything against Haku's attacks, as they are so fast and come from so many directions at once that it's impossible to see all of them. If they should try to attack Haku while he's within a mirror, he can simply move to another mirror before they've even noticed. If Haku completely surrounds his victims with mirrors, such as the dome he uses against Sasuke, then they are effectively trapped; only allies working from outside the dome stand a reasonable chance of saving them. Even targets who manage to keep their distance from Haku are not safe, as he can simply form a mirror next to them, allowing him to quickly travel to and attack them.
- The full name of this technique is "Secret Technique: Demonic Mirroring Ice Crystals" (秘術・魔鏡氷晶, Hijutsu: Makyō Hyōshō).