Anbu Commander

This shinobi is seemingly the commander of Konohagakure's Anbu.

Background
He and another Anbu accompanied the Third Hokage in infiltrating a secret bunker with the intention to find out who was behind the disappearances of shinobi from their village. After they disarmed the traps, they confronted the person behind the acts and discovered it was Orochimaru. Having been caught, the sannin attacked the Anbu and Hiruzen, giving him an opportunity to escape and flee the Land of Fire.

Appearance
He is dressed in a white cloak and black trousers with bandages tied around his right leg, arm-guards, gloves and black sandals. He also has brown, spiky, hair and wears a mask with a dog motif inclusive of pointed ears, detailed eyebrows and three, thick stripes with two along either sides of his cheek and one on his forehead. He has also been depicted at times with a line running across the right side of his mask to its eye hole.

Abilities
The fact that he is the commander of the Anbu, which consists of some of Konohagakure's most skilled shinobi implies that he is a very powerful ninja. He is very observant, seen when he recognises that Pain's chakra-levels must be immense and that he is controlling the bodies used to destroy Konoha by chakra alone. The fact that he carries a sword hints that he is skilled in kenjutsu.

Pain's Assault
During Pain's assault on Konoha he reported to Tsunade that the enemy's strength was estimated at three battalions in total by the analysis team. On Tsunade's orders he assigns squads to protect Shizune while she researched and the interrogators while they tried to acquire more information. He later accompanies Shizune, Inoichi and Ino who had broken off from the main group in order to uncover the mystery of Pain together. However the Human Path was able to slip into his guard and interrogate Shizune after taking her captive, killing her in the process. Later he, along with Inoichi and Ino joined Shikaku, Shikamaru and Shiho, carrying Shizune's corpse.

After the battle between Naruto and Pain, he informs Shikaku of the emergency meeting which he attends along with Danzō Shimura, and the Konoha Council.

Five Kage Summit
After the invasion, the Anbu commander is one of five Konoha villagers to be summoned before the Fire Daimyō to discuss the village's response and reconstruction. With Tsunade in a coma, Danzō suggests selecting a new Hokage. Though silent in the meeting, he is shocked when the Fire Daimyō announces that Danzō was to become the next Hokage.

Trivia

 * In Part II of the anime, he is initially shown wearing a standard black cloak. This was later corrected when he is shown at the meeting with the daimyō.