Nickname: Black Flash of Kumogakure
Darui is fairly tall and has a dark skin tone, slightly bulbous nose, a lazy look in his eyes and white, shaggy hair which covers his left eye. He wears a high-collared, sleeveless uniform with loose fitting pants, bandages on his wrists and the one-strap-over-one-shoulder Flak Jacket of a Kumogakure shinobi. Darui also has stylized characters for Water (水) and Lightning (雷) tattooed on his right and left shoulders respectively, denoting his chakra's nature affinities, Water Release and Lightning Release, as well as the fact that he has a kekkei genkai, the Storm Release. The tattoo on his left arm also signifies that he has inherited the Third Raikage's technique. Darui also carries a broad, foldable, cleaver-like blade, which he carries on his back.
Darui is portrayed as being easy-going and mellow; when compared to the Fourth Raikage's over-the-top exit through a window, he tells C that he will just use the door. While having a laid-back demeanor, Darui isn't lazy, leaping to the Raikage's defense when the bodyguards of the other Kage overreact to the Raikage's actions. He also has a habit of referring to things or events as being "dull" (だるい, darui) a play on his name. Darui is also very apologetic, even apologizing for other people's actions, a trait he had never noticed himself; this attribute led him to say "sorry" (すみません, sumimasen) just as much as the word "dull". He is also very loyal to the Raikage who considers Darui his "second right hand". He also often time addresses the Raikage as "boss" rather than "Raikage-sama".
Village of Birth: Kumogakure
Village of Alliance: Kumogakure
Darui and C were chosen to escort the Fourth Raikage to the Kage Summit in the Land of Iron. Once they arrive and the meeting begins, Darui and C comes to the Raikage's defence following his outburst, blocking the attacks of the other Kage's bodyguards. They return to their posts after things settle down, only to again come to the Raikage's side when Zetsu appears. Zetsu reveals that Sasuke Uchiha, Killer B's captor, is nearby, so Darui and C accompany the Raikage in tracking Sasuke down.
When they locate Sasuke and his team, Suigetsu charges at C. Darui blocks his attack and they start to exchange blows with their respective swords. Darui is ultimately victorious, as he imbues his sword with lightning to pin Suigetsu to a wall. He then tends to C - who has been knocked unconscious by Sasuke - and they both watch the Raikage grow increasingly reckless in his fight with Sasuke. The Sunagakure delegation soon arrives to provide assistance, and Darui joins forces with them in bombarding Sasuke. Using Susanoo, Sasuke survives their assault and destroys the structural supports of the building they're in; Darui is protected from falling debris by the Fifth Kazekage. They reunite with the Raikage and C and return to the Summit hall, where Tobi explains his Eye of the Moon Plan to them. As part of his explanation he reveals that B only pretended to be captured, which does not surprise Darui. After the formation of the Shinobi Alliance, Darui joins the Raikage in searching for B. They are drawn to the site of his battle with Kisame and arrive just in time for Darui to stop Kisame's attempt to cut off B's legs. When Kisame is "eliminated" they all return to Kumogakure. Despite Darui's desire to rest, Mabui requests a report of what has happened since they left. Darui later attended a war meeting.
During the Fourth Shinobi World War, Darui is placed in charge of the First Division of the Allied Shinobi Forces. His sent to the border of the Land of Lightning to defend against an approaching portion of the Akatsuki forces. Before the opposing army makes landfall, Darui launches the first attack, using his Lightning Release: Black Panther technique to electrocute dozens of White Zetsu Army clones. As the battle rages, Darui confronts the revived Gold and Silver Brothers. He apologises for needing to defeat them and tarnish their reputations further. As the battle ensures he is joined in battle by Samui and Atsui and the brother reveal their weapons of choice: the Treasured Tools of the Sage of the Six Paths. As they battle the brothers, a few Zetsu clones try to ambush them but they are saved by Atsui's attack. He tries to stop Atsui before he rushes off to face Kinkaku and Ginkaku but watches on as both him and Samui are hit with the Kōkinjō and have their word souls (言霊, kotodama) severed. He watches in shock as Atsui is sucked into the Benihisago and Samui is taken hostage. As Darui apologises to Samui for what he was about to do, he severs Kinkaku's arm and uses his Storm Release: Laser Circus attack hitting both Kinkaku and Ginkaku who is shocked to see that the missiles from the attack were guided. This assault ends somewhat in defeat as Samui is absorbed into the Benihisago and Darui is hit with the Kōkinjō and his word soul severed with the Shichiseiken.
Having learned how the tools work by watching what happened to Atsui and Samui, Darui knows he can avoid being caught in the Benihisago by not saying his most-said word: "dull" (だるい, darui). However, he inadvertently utters the word by saying, "Ore wa Bosu no migiude da. Ruijihin janē!, I'm the Boss' right arm. I'm no imitation!)". As he is sucked in he says "sorry" (すみません, sumimasen) three times, making that his most-said word and thus stopping the suction. After his escape, Darui uses his sword and is able to knock Ginkaku into the Kōkinjō and commandeer the Shichiseiken and the Benihisago. After looking at his changed most said word, he realises that he was very apologetic by nature and says that he'll accept that. He then launches a new tactic and distracts Kinkaku by throwing his sword at him and then follows up with his Laser Circus technique again which buffets Kinkaku, giving him a chance to sever Ginkaku's word soul with the Shichiseiken.
Ginkaku then says his most used word, "Kinkaku" (キンカク), and gets sealed inside the Benihisago. As he begins to suffer from the massive chakra drain of the Treasured Tools, Darui witnesses Kinkaku turn into his six-tailed form and rampage through the battlefield. To stop Kinkaku, headquarters sends him the Kohaku no Jōhei and Team 10 to provide support. While Shikamaru and Chōji distract Kinkaku, Ino uses her Mind Body Switch Technique to take possession of Kinkaku's body.
Darui then calls out to Kinkaku and Ino forces Kinkaku to respond, activating the Kohaku no Jōhei and sucking Kinkaku in.
As Kinkaku is sealed he wonder how he and sibling could've been defeated by "copper" pieces, and Darui tells him that when you have a bunch of copper coins, they can be worth just as much as a gold coin. With the Kōkinjō getting sealed along with Kinkaku, Darui has no way to use the Benihisago. He nevertheless hangs onto it, hoping to find a way to free Samui and Atsui. In the meantime, he helps subdue the revived Kakuzu. By nightfall Kakuzu and the rest of Akatsuki's forces have been dealt with. Before they can claim victory, Tobi appears on the battlefield with the Demonic Statue of the Outer Path. While the Statue wreaks havoc, Tobi confronts Darui and tries to take the Benihisago and the Kohaku no Jōhei. Fearing Tobi's intentions, Darui and Shikamaru try to stop him, only to be attacked by the Statue. They are saved by Chōji and Kitsuchi while Tobi escapes with the tools. They start to retreat at nightfall.
The next morning, Darui and the other shinobi are made to stand apart inside circles until Naruto can arrive on the battlefield and weed out the impostor shinobi. Darui later expresses his disbelief that the Raikage had actually agreed to let the jinchūriki out of confinement.
Due to Darui's high mastery over lightning release, he can perform all techniques with only a single hand seal.
Darui is proficient with water and lightning release techniques, and is able to use two separate techniques of the natures simultaneously. He uses Lightning Release: Wave of Inspiration, together with water release techniques to let electricity flow through the water, making the technique deadlier. He is also able to combine these two separate natures to create the kekkei genkai known as Storm Release which creates beams of light that flow like water and can be freely guided like missiles.
He is also able to use the black lightning technique, a special form of lightning passed down to him by his teacher, the Third Raikage. With the power of the "black lightning", he can use techniques such as the Lightning Release: Black Panther to immobilize and or kill several enemies. According to one of his comrades, he is the only person to have inherited the Third Raikage's technique.
Usually, Darui wields a broad and fairly long sword that is peculiar in comparison to others swords in that it folds in two to be sheathed and unfolds when in use. He has shown exceptional skills in kenjutsu, as he was able to clash with Suigetsu Hōzuki's Kubikiribōchō and easily overwhelm and pin him to a wall with his lightning imbued sword. He was also skilled enough to literally disarm Ginkaku and Kinkaku during their battle, and knock Ginkaku into Kinkaku's Kōkinjō while quickly seizing the Shichiseiken and Benihisago.