Leonardo (The Next Chapter)

Leonardo, often referred to as Leo, is one of the main protagonists of the Teenage Mutant Ninja Turtles: The Next Chapter and the leader of the Ninja Turtles. He is also the youngest of the four brothers, who all share a home in the underground sewers of Manhattan, New York City. Leonardo is the adoptive son of Master Splinter and adoptive brother of Karai. He belongs to a diverse family consisting of three other mutant turtles who are his biological brothers: Raphael, Donatello, and Michelangelo. Splinter, a human-sized mutant rat, serves as the Turtles' adoptive father and sensei.

Appearance
Leo is an fern green colored anthropomorphic mutant turtle ninja warrior. His eyes have cobalt blue irises with black pupils, but like his brothers when they are shown fighting or being stealthy, they disappear, leaving his eyes white (similar to the 2003, 2012, and 2023 incarnations). He wears a royal blue bandana mask where the tails length range between Donnie and Mikey's. Leo is the most skilled fighter, and he doesn't have much changes to his physical appearance like all his previous incarnations. His height ranges between Raph and Donnie's. His ninja gear includes brown knee pads and elbow pads, and beige rolled bandages wrapped around his wrists, ankles and fingers. Leo's hands have two fingers and a thumb and has 2 toes (likes his brothers except Michelangelo who has three webbed feet).

Personality
Leonardo is the leader, whose key attributes consist of honor, sensitivity, patience, and encouragement. He is the most "spiritual" of the four brothers. Despite being a teenager, he acts kind of like a grown-up due to all his seriousness, but can still have fun with his brothers.

Of the brothers, he has the closest bond with Splinter, often going to him for help and attempting to follow his orders to a T (at least when his brothers aren't out causing trouble, forcing him to go along with their antics). While responsible, Leo can still be sucked into trouble by his brothers out of his own curiosity or his sense of duty to keep an eye on them.

Leo has a strong sense of honor and ethics, along with being a dedicated follower of the Bushidō code.

One of Leonardo's most prominent qualities is his determination to believe the best in people, even potential enemies (i.e., Bebop, Screwloose, Karai, Rocksteady, Wingnut, Leatherhead, Slash, Mondo Gecko, Genghis Frog, and Man Ray). This trait can cross over with being naive, though, as his trust almost led him to siding with the Shredder the first time they met. Even so, he is willing to give even people who betray him a second chance if he sees good in them, such as with Karai. His trust in her was shaken multiple times due to her inability to pick a side, but he still risked his life to save or assist her.

Leo may be the most mature but don’t be fooled. When Leonardo loses his temper, he would have emotional outbursts just like Raphael would if he was upset. Sometimes his explosive outbursts can be more violent and raging than Raphael’s.

History
Eleven years before the events of Teenage Mutant Ninja Turtles: The Next Chapter, Leonardo and his brothers were once ordinary turtles. When they were infants, the benevolent Hamato Yoshi purchased the four as pets. When their soon-to-be father walked passed a strange man, he felt something odd about him and followed. Unfortunately, Yoshi gave away his position when he accidentally stepped on a brown rat's tail. The Kraang found him and attempted to kill him, but Yoshi fought back hard. During the scuffle, the aliens dropped a container of mutagen, Yoshi, having to have stepped on that rat, thus mutated into a humanoid brown rat by the name of "Splinter", While Leo and his brothers, after having been in contact with Yoshi and the clerk of the pet store where they were bought, mutated into humanoid turtles. Yoshi raised the turtles as his own children and to train them in Ninjutsu.

Splinter knew they would never be accepted in society and with the Kraang hot on his trail, the five of them lived in an abandoned water tower and a warehouse avoiding detection. During all of these trials, Splinter and the Turtles bonded and after he noticed the baby turtles trying to copy his Ninjitsu training, Splinter decided that there was an opportunity to turn this new life he was thrust into to his advantage, Taking one of his favorite books about the Renaissance art named them after the Artists he admired the most.

After last fight against the Kraang in the sewers in Splinter overheard the Kraang talking about how it became impossible for them to track Splinter and the Turtles there, Splinter decided to remain there. Thus making it that Splinter had found the safe environment where he could raise his adopted sons. Knowing the world would be dangerous and there would be a time where they want to explore the outside world, Splinter started to train the boys in the art of Ninjitsu. Eventually, Splinter gave Leonardo his katanas, "for one with courage and keen skill."

Abilities
Leonardo is the most stern, serious, focused, disciplined, responsible and among his brothers, being able to take on much larger opponents quicker and more easily in addition to coping with hectic stress. Like his brothers, Leonardo has been extensively and intensively trained by Splinter to become a highly skilled ninja warrior, but to a much greater extent. During his training session with Splinter and his brothers, Leonardo managed to be the only one to land a hit on Splinter. Throughout the series, Leonardo's martial skills increased even further, as he can take on Karai and best her in skill, and eventually defeated his arch-nemesis, Super-Shredder in one-to-one battle. After becoming a sensei, Leonardo's martial art skills is enough to nearly match his mentor, Splinter. Because of this, he has great knowledge of pressure points as he used it on Raphael to impale him during their argument fight and other martial art techniques, making Leonardo not only the best fighter in the ninja turtles team, but also one of the most skilled fighters in the film.

Weapons
His signature weapons of choice here are purely dual twin katana (刀) swords, which he uses and fights in the Niten Ryu (also known as Niten Ichi-ryu "The strategy of two heavens as one") style of kenjutsu, making him a skilled and excellent swordsman (although referred to as katanas, Leonardo's swords are actually much more closely modeled around the "Ninjatō" (忍者刀 ninjatō), (also known as ninjaken (忍者剣) or shinobigatana (忍刀)), a fictional sword similar to the katana, depicted as being a ninja's version of the weapon. It is usually straight-bladed, has a square guard, and is shorter than katana. The handles have the same dark red and gold color that Raph's sai and Mikey's nunchucks have. Unique from his brother's weapons (Bo-Staff, Sai, and Nun-Chucks) Leo's weapons are the only ones specifically designed to deliver killing blows, though Leo is much too honorable to want to do so. You know what they say, "two swords are better than one."

In this incarnation, he's still very much learning to be a master swordsman (especially when compared to the 4Kids Leonardo). However, he's showing encouraging signs of it.

It's is implied that Leonardo has multiple identical katana swords stashed at the lair, such as when he is shown returning to the Turtles' underground lair after a fight with only one katana (having lost the other katana during the brawl) but is later shown with two katana swords sheathed on his scabbards.

Typically, Leonardo wields a pair of katana; one Daitō (大刀), a catchall word for the larger sword in a daishō pair (the word itself refers to the length of the blade, which was usually 70-90 cm) and one Shōtō (小刀) or Kodachi (小太刀), a catchall word for the shorter sword in a daishō pair. ("Kodachi" can also be used to refer to a blade that was similar to a wakizashi, but designed to be used by itself rather than in combination with a katana.), which, like his brothers with their chosen weapons, he is highly skilled with.

Trivia

 * Leonardo is named after the famous Renaissance master, Leonardo da Vinci.
 * Leonardo's name is Italian, meaning "Strong as the Lion/Lion-Bold".
 * His name in Katakana is レオナルド (Reona​rudo).
 * Given the fact that he was adopted by Hamato Yoshi/Splinter, Leonardo's full name would be "Hamato Leonardo", or "Leonardo Hamato" in Western naming order.
 * Niten Ryu ("Two Heavens Style"), is described as Leonardo's weapons, but it is in fact the name of a fighting style for Japanese swords, and not a weapon. A two-sword set-up is properly known as a daisho, (大小). Niten Ryu, instead, is short for Niten-ichi Ryu, (二天一流), a two-sword style developed by legendary samurai Miyamoto Musashi.
 * Leonardo's swords, whilst being referred to as "Katana", are actually "Ninjatō" (忍者刀 ninjatō), (also known as ninjaken (忍者剣) or shinobigatana (忍刀).
 * The existence of the ninjaken has been up for debate for many years.
 * According to the Concept Art of Leonardo's Katana, "Niten Ryu", one sword is longer than the other, and a Tanto blade is concealed within the hilt of the "Daito" (Long Sword), and a "Kogatana" (Mini Tanto) is concealed within the Saya's (Scabbard's) binding wrappings, all as secondary, auxiliary weapons to his Katanas.
 * His mastery of Ninjutsu includes: Seishin teki Kyoyo, Taijustu, Qigong, Kenjustu, Shurikenjustu, Kayakujustu, Shinobi-iri, Sui-ren, Boryaku, Kyuudou, and Intonjutsu.
 * Leonardo seems to be the most educated (out of the four brothers) about Japanese culture and etiquette:
 * He understands Japanese when spoken to and is able to speak in this language to some extent.
 * He knows, at least basics, of Japanese etiquette (i.e. he bows to Master Splinter)