Might Guy (マイト・ガイ, Maito Gai) is one of the main characters of the series. He is the leader of Team Guy, which consists of Rock Lee, Neji Hyuga, and Tenten.
Known for his thick eyebrows, green jumpsuit, and shiny bowl haircut, Guy often refers to himself as "Konoha's Sublime Green Beast of Prey" (木ノ葉の気高き碧い猛獣, Konoha no Kedakaki Aoi Mōjū). Throughout the series, he has displayed many unique traits that are meant to be seen as corny and old-fashioned, a reference to common clichés of "youth" (青春, seishun). Guy is also known for going on about the "Power of Youth".
Guy is best known for his "nice guy pose", which consists of giving a thumbs up, winking, and smiling with teeth so white they give the proverbial "ping", a trait which rubbed off on Lee. This action is often used by both Guy and Lee to indicate commitment to a statement they had just made, their highest form of a promise.
Guy is on good terms with all of his students, but takes particular interest in Rock Lee, who reminds Guy of himself in his youth in retrospect that both are considered losers and have to work hard to achieve their goals. As such, Guy puts much more interest in Lee's training than Neji's or Tenten's, continuing to train Lee long after the others have retired for the day. Because of this, and due to Lee's unyielding desire to master the art of taijutsu, the two have developed a father-son relation that has pushed Guy to teach Lee a number of dangerous and forbidden techniques, giving the stipulation that Lee can only use them under specific circumstances. Although Guy knows of the dangers that teaching the techniques to Lee entails, Guy wishes for Lee to be able to prove himself to be a splendid ninja, and, as such, turns a blind eye to the repercussions. However, overall, Guy is a very attentive and dedicated instructor, who does everything in his power to make sure that all three of his prized students receive proper instruction in their own particular fields.
Guy, and, by extension Lee, lives his life by his own "My Rules" philosophy, which involves setting tougher goals for failure so something good comes of it. For example, he vowed to walk 500 laps around Konoha on his hands naked if he lost an intense game of rock, paper, scissors with Kakashi.
Guy's teacher-student relationship with Lee also carries distinct attributes, such as when Guy will punch Lee for a slight infraction of a rule. After Guy assigns Lee an arduous training task as punishment, meant to recapture Lee's focus and discipline, the two may then burst into tears and affectionately embrace, in brief regret for the strong blow Lee was given. Guy often attempts to act in a similar way towards his other two students, although Tenten is usually resigned and more willing to take part in his antics than the more stoic Neji.
Guy is the self-proclaimed rival of Kakashi Hatake, though the latter is indifferent to the former's annoyance. Guy also often challenges Kakashi to random contests of skill. Their competitions seem to, in part, be founded on the fact that the two are polar opposites. Guy has shown to be more easily excited compared to the more laid back Kakashi. He also relies mainly on taijutsu, in contrast to Kakashi's ninjutsu specialisation, and had to work tremendously hard to reach his level of prowess, whereas Kakashi's natural talent and Sharingan made it easier for him to improve. Nevertheless, both men are great friends and also have the utmost faith in each other.
Guy can't handle sea rides and easily gets seasick when he has to travel by boat or ship.
Guy is a tall and well-built man with high cheek-bones, thick eyebrows and black hair cut in a bowl style. Guy also wears a green jumpsuit, orange striped leg warmers and the standard Konoha flak jacket, though it's normally unzipped. His forehead protector is on a red cloth and is worn around his waist like a belt.
When he was a genin, he wore the same style of clothing with bandages wrapped around his hand and a brown scarf tied around his neck. His hair also had the shape of his signature bowl-style though a bit longer and shaggier, framing the side of his face.
During his time as a genin, Guy already had talent in taijutsu. As an adult, Guy has become an excellent taijutsu master.
Because of his extreme and unorthodox training regimes, Guy has achieved incredible physical prowess and stamina. His tremendous strength allows him to leave a gaping hole in a wall with a single kick.
Guy is able to open all of the Eight Gates. His mastery over the technique allows Guy to be able to instantly open up the first seven gates, without the need of opening previous gates.
Once he opens these gates, Guy has access to several kinjutsu derived from it. With the sixth gate, Guy can use the Morning Peacock, a series of punches so fast that his hands were set ablaze by sheer speed and friction. With the seventh gate, he can use the one-hit kill Daytime Tiger, which is strong enough that Kakashi had to resort to using his Mangekyō Sharingan. From what has ben shown of the eighth gate, Guy can use the Night Guy, a powerful single kick.
Guy's personal weapon of choice is the nunchaku. His mastery however has not been shown in the spin-off.
Although Guy relies mostly on taijutsu, Guy is able to summon nin-tortoises like Ningame.