Sen Uchiha was born on march 7 six years after the fourth Shinobi World War.Sen became an Orphan after the death of his mother the day he was born and his farther left them the day of his birth as well and so him and his brother were left alone and travelled the land of fire until the reached the hidden leaf. Without a home and food Hira decided to steal food from others until he was captured by Kakashi Hatake. Kakashi seeing great potential in Hira he decided to assign him to a team and he was put with Yashi Hyūga,Sami Nara, and Haru Aburame as there team captain. As for Sen he was assigned to his team with Taichi Uzumaki and Hikari.At first Sen was a very quiet person who did not talk or communicate with others not even his squad mates the only person he would talk too was his brother. after a mission to the hidden grass village they were attacked by an S-rank ninja who was on the run and Captured Sen form the team. as Sen sat at a cave thinking no one would come to save him not even his brother and then Taichi attacked the rogue ninja and got badly injured thinking how Taichi came back for him made him happy and he activated his Sharingan using its power to help Taichi and defeat the rogue nin. After that day Sen and Taichi became the best of friends. five years past and the Chūnin Exams came and Sen was up against Yuki Senju knowing his clans history with the Senju and how they were always at war with each other Sen decided to use his sharingan (which was now fully matured) he was a master of genjutsu and was able to put Yuki in one. hover it was just a wood clone and Yuki made an entire forest grew and calling Sen a weakling with no life or friends made him sad and made him remember his past and his mother and farther until Taichi yelled at him to not listen to her making forget his past and move on which made him activate his Mangekyō Sharingan and put Yuki in a more powerful genjutsu he won and moved on to the finals.during the final round Sen saw Hira and how he wanted him to win. Sen feeling overjoyed gave him the power to use the Susanoo ribcage Hira seeing this began to worry for Sen and told him to not use the susanoo until he was ready. Not obeying his brothers words Sen used the Susanno and hurt Taichi and Hikari. feeling bad Sen left the village and Yuki joined him for unknown reasons and then they meet to others on the way. Fuku and Kawa both were missing nin Fuku from Amegakure and Kawa from Sunagakure they met each other in a fight and decided to travel and now were apart of Sens team called Eternal. After the war Sen came home and is now married to Yuki Senju. After the death of Kohaku and Tsubasa awaking from his coma he became the Seventh Hakkinkage.
in part 1 Sen is a very short person for his age with black hair, a black shirt with the Uchiha sigh on the back and bandages wrapped around his arms and legs. In part 2 Sen has become very tall and his hair has gotten a bit longer he no longer has bandages around his arms and legs.and he wears a red and black cloak with the Uchiha sigh on the back and a dual-sword holder on his back.
in his first appearance Sen had a very quiet and nervous personality not talking or interacting with any of his classmates or teachers at the academy and when he was assigned to team Kakashi he was still very quiet but also sad knowing that him and his brother would not see each other that much because he would start going on more missions and spen less time helping Sen train. But after his mission to the hidden grass village and was captured by a missing nin and Taichi saved him after that Sen became a happy person. but some time after the chūnin exams he stared acting strange and stated taking about how power is every thing. Soon after that he left the village in order to destroy it after he learned the truth about his farther.
Being an Uchiha Sen has become a master at Fire Release knowing more than two hundred Fire Release attacks. And is very good at Lighting Release knowing sixty six Lighting Release moves. and he is also a master at Blaze Release.
Since he has awaken his Mangekyō Sharingan he is granted with the three abilities of the Kekkei Genkai; Amaterasu,Tsukuyomi, and Susanoo. Sen being a member of the Uchiha is skilled with Blaze Release.
Sen has sighed many contracts with many animals these include Snake,Wolf, and Hawks all of which have helped him in many situations. But the ones he always trust are wolfs. Every since he and his travels in the land of fire with his brother wolfs would always seem to help the such as telling them ways to go and getting food for them which is way Sen will always stay loyal to them just as they have to him.
after learning the truth about his farther Sen returned to the hidden leaf and killed an went to the Uchiha clan finning his way into his home he took his brother's sword and claimed it as his own soon after that he became an amazing swordsmen.
Sen is an amazing user at genjutsu even without an matured Sharingan. this was proven in his battle with Yuki Senju. his first try she saw a giant sun falling down on her making her feel as if she was on fire. when he activated his Mangekyō Sharigan she saw her forest(which he had made with her Wood Release) on fire and the smoke suffocating her. Sen is at the same level as Itachi Uchiha in genjutsu.
Sen activated his Sharingan the day he was captured and Taichi Uzumaki tried to save him but got badly injured in the process. Sen, now knowing that people do in fact care for him, activated his Sharingan.
Sen awakened his Mangekyō Sharingan the day he fought Yuki Senju at the Chūnin Exams, when she made him depressed. As a result, Taichi yelled at him and told him to keep fighting, causing him to initially activate his Mangekyō Sharingan for the first time.
After many years of training, Sen learned the secrets of Space–Time Ninjutsu. He was able to learn the Flying Thunder God Technique, which essentially allowed him to teleport to any location with untraceable movements had through the use of special seals. By throwing kunai that had the seal attached to them behind enemy lines, Sen could wipe out an entire platoon in the blink of an eye.