The two brothers started fighting as Riku and his mother ran away. Hayato decided to take his fight to the forest getting away from Konohagakure. The forest around them eventually lead into a open area of a green plain of grass. This was when Hayato fully started to engage in the fight. Hayato charged at Reo with the sever release on his hands. Hayato expanded his sever release on his hands forming what looked like claws.
Hayato: Sever Release: Claws of the Beast.
Reo saw this and attacked with the sword in his right hand coming down on Hayato. Hayato grabbed the sword as it came down. Hayato felt the pain from the combination of the Kiba and the sever release. He knew that the sever release that his brother used wasn't as strong but he underestimated the Kiba combined with it. He pushed off the sword from his hand as some blood started to drip from that hand but he ignored it as he used his left hand claw to swipe at his brother's chest. Only to see that his brother blocked it resulting in his other hand being injured as well. Hayato realized he needs some distance and he needed to be either trickier or faster.
Hayato: Sever Release: Crescent Slash
A slash of sever release came out of his hand and went to Reo as he was getting more distance Reo swiped one of his swords at the crescent slash and it was destroyed. He started firing more of the crescent slashes as the last one shot at Reo he saw that Hayato was gone from that area. He heard wind and lightning behind him and turned and saw Hayato behind him. Reo slashed at it only to see that it was a substitute jutsu as he slashed the Kiba through the piece of wood that replaced Hayato. Hayato then went from the other side again but before his attack connected he received the other sword that didn't destroy the substitute the slash came down on Hayato's chest which he avoided but as he dodge it resulted in his arm being cut and bleeding profusely. He made some distance shooting mre crescent slashes.He then bit his thumb did some hand signs and pressed his hand to the ground.
Hayato: Summoning Jutsu.
A puff of smoke appeared in front of Hayato and when the smoke cleared a small white owl with black spots on it owl appeared on his shoulder. The owl looked harmless but soon it went into action. The owl opened his eyes and stared at Reo the owl flew up from Hayato's shoulder and started to create a dome of wind around Reo cutting off his eyesight and hearing. Reo started to attempt to cut through the dome using his swords but the dome was constantly repaired as the owl kept channeling wind release chakra into the dome.
Hayato used the dome from his summoned animal to his advantage and started to fire some crescent slashes into the dome from all around the area. Reo seeing the slashes as they appeared in the dome slashed at them cutting them down. Hayato then decided that he should use the hindered vision and hindered hearing of his brothers to attack him in the dome with his claws as they were stronger than the crescent slash. Hayato did what Naruto did in the finals he decided that he would attack from under his enemy.
He got to the area under Reo and attacked from the ground his sever release claws. He was able to slash at his brothers calves causing his calves to start bleeding a lot and got a slash in response to his head but as the sword was about to hit his head it stopped. Hayato saw the sword coming to his head and responded with a hit of his sever release claw to Reo's attacking arm. As Hayato hit Reo's attacking arm he came face to face with his brother as he saw his brother in tears.
Reo: Thank you for releasing me from the genjutsu brother I will not be forced to sin anymore. I am so sorry brother for what I did I should have never done what I did.
Hayato: What?
Reo: I believed that I had a chance to change the clans traditions but I failed.
Hayato: What really happened?
Reo: After you were banished I saw the opportunity to change the clan so I took it. I made a deal with the Mizukage that if they help to take out the elders and the supporters of the traditions that we would leave the village and not cause any damage to Kiri. They told me that I would help them kill the elders. They gave me the Kiba and some troops to kill them. I decided that I would not turn back and I would do it. It was a very bloody fight, I took the responsibility of killing father. I kept thinking if this was the right choice through the whole event. But when I went to leave the house to report outside was the Mizukage. There was a masked man behind him that then placed me under a genjutsu that I couldn't get out of. They forced me to kill the rest of the clan and after hunt down the rest of the clan against my will.
Hayato: What no one is left alive?
Reo: No one we are the last.
Hayato; What about the Mizukage and this masked man?
Reo: From what I saw the masked man controlled the Mizukage under a similar genjutsu. The reason the genjutsu was so strong was he had a sharingan.
Thanks for the support