The mighty beast of battle, Might Guy is the green spandex-wearing shinobi with bushier eyebrows than Rock Lee. While a somewhat goofy sensei, he is a master of taijutsu and was considered by Madara Uchiha to be the strongest shinobi of all. With the resilience to bring himself to the brink of death and still keep going, Guy is undoubtedly a legendary shinobi in the Naruto universe.
Might Guy is the son of the Might Duy. Duy was insultingly dubbed the "Eternal Genin" by the Leaf Village due to his lack of skill with ninjutsu or genjutsu and sub-par taijutsu. However, instead of being discouraged by this, Duy was always optimistic and grateful that people even knew him at all. When Guy entered the Ninja Academy, he was also not very skilled. As with Rock Lee when he was younger, Guy had no talent and or confidence in himself. However, Duy encouraged him to become stronger through diligent training and hard work, referring to that belief as "youth" -- the guts and drive to keep going no matter what.
Even though the village looked down on his father, Guy idolized Might Duy and fought anyone who made fun of him. Duy urged Guy not to be upset and remember that real strength came from defending what was important. Guy took these teachings to heart and used them to become a taijutsu master and an extremely powerful shinobi. When Guy became skilled enough at taijutsu, Duy passed on the technique to open the Eight Inner Gates to his son. Duy developed this technique over 20 years and eventually used it to save Guy's team from the Seven Ninja Swordsman of the Mist at the cost of his life.
By adulthood, Guy is a taijutsu master, using the Strong Fist style that adapts his attack patterns and battle tactics to best handle the situation with unorthodox yet effective strikes. Guy has conditioned himself to the peak of physical prowess by constantly challenging himself through various surreal methods of arduous training. Because of this, he's able to perform seemingly inhuman feats without the aid of chakra enhancement. His sheer speed and raw strength as well as his incredible stamina and recovery rate allows him to continue fighting even in the most extreme situations and conditions.
With the ability to open all chakra gate limiters and the Gate of Death, Guy exhibits incredible power. Even Madara himself believed Guy to be unsurpassed in physical strength. During their fight, Guys is able to utilize and open all Eight Gates, his mastery over this ability allowing him to instantly open the first seven gates without having to open them individually. Opening each gate unlocks different physical and mental abilities and enhances them to their fullest potential.
Guy has created several different techniques that can be performed with each gate that is opened. With the first and third gates, he performs the pile-driving Front Lotus and punch-heavy Reverse Lotus. With the sixth gate, Guy produces a rapid series of punches that ignite through air friction, a technique he calls Morning Peacock. The seventh gate produces a technique of concentrated air pressure that Guy launches at an opponent and violently expands on impact, a move called the Daytime Tiger. When Guy opens the eighth gate, he can use a technique called Evening Elephant that creates powerful shock-waves with his punches. In his most powerful technique, Night Guy, a single kick is released with such speed that space distorts around him.
The more gates Guy opens, the more damage his body takes as well. Only his extreme training allowed him to handle opening the gates for long periods of time as well as immediately adapt to the immense pain of the eighth gate. Although he sustained permanent damage from the injuries of the war, Guy was able to adjust to his disability through rehab and is still as powerful as ever.
While quite the kooky character, Guy exhibits abilities and strength that are unique to him alone. Even though he is known for his mastery over taijutsu, Guy is able to use some ninjutsu like summoning Ningame the tortoise and can dispel high-level genjutstu. He's skilled with a variety of ninja tools that make him quite the weapons specialist. Overall, Might Guy is an amazing shinobi with strength and skill that is like no other. No matter what he does, Guy always lives in the springtime of youth!