Ninken

are eight ninja dogs that Kakashi summons. All of the Ninken have a face-shaped design on their backs called Henohenomoheji (へのへのもへじ), which is the sound made when all the characters in the face are put together. Appropriately enough, children use this design as the face for their scarecrows, which is Kakashi in Japanese. The dogs themselves also seem to resemble other characters in the series, with two closely resembling Naruto and Gaara.

They are mostly used for tracking purposes, such as when Kakashi needed to find Sasuke Uchiha and Naruto Uzumaki during the Sasuke Retrieval arc. He can summon them separately, as he does so with Pakkun, or all together. He can also summon them for special purposes, like he does with his. With this technique, the dogs can travel through the ground following the scent of their target, emerging when the target is found and holding them in place.

In Part II it is revealed that most, if not all, of the ninja dogs can speak, though Pakkun was the only one to do so for the majority of their appearances. The dogs are also shown capable of walking on water. Currently, the only named dogs are Pakkun and the large bulldog named - "Bull", who currently accompanies Naruto, Hinata and Yamato.