The two of them went to the first floor for their match. Kabuto was a silver hair guy with black eyes and glasses and looked to be in his early twenties. Kabuto stood at his spot and Riku did the same both showing respect to their opponents. At that time Ryu walked into the second floor.
Ryu: Hey sorry I am late.
Kakashi: Oh you are just in time for Riku. But I am surprised you showed up in general. I thought you would be either drinking in the diner or practicing your swordsmanship.
Ryu: Hey what can I say I took an interest in the kid.
Soon a guy that looked like an older version of Rock Lee walked over to them.
Older lee: Hey Kakashi, Ryu you wanna spar later.
Ryu: No thanks Guy go do that with your rival over there.
Guy: Oh come on you never join our fights.
Soon after Hayate started the match. Riku summoned Asami in sword form did his usual of applying his sever release to the blade and the blade purifying giving the blade a green and blue glow. While Riku did the Kabuto channeled his chakra to his hand giving it a blue glow forming what looks like a blade. Riku looked at the blade and recognized it as a medical nin technique called chakra scalpel a technique to cut precisely through flesh. The scary part of the technique was that it could cut inside ones body without making a wound on the surface. So a skilled medical nin could injure someone in a big way without making a wound on their skin.
Kabuto: The sever release. Very deadly when fully matured but I can tell you aren't at that level yet sadly.
Without answering Riku started to attack Kabuto. Riku was low to the ground and had his sword on the right side of his body near his hip. He rushed at Kabuto while remaining low and when he got to Kabuto he swung his sword horizontally at Kabuto's stomach. Kabuto dodged the attack as soon as he saw it coming but he wasn't fast enough and got a clean cut through his stomach revealing blood. He retreated a few steps back and started to close the wound but not completely heal it. As Riku continued to go after him.
Kabuto: Seems that I should stop underestimating you just because you are the youngest here.
Kabuto finished closing the wounds on himself as he started to chanel the chakra scalpel technique in both of his hands. Riku closed in on him again and sliced from bottom to top this time but instead of hitting he was misdirected by the chakra scalpels and the sword went to the right giving Kabuto an opening. He attempted to cut Riku but what happened was Riku avoided it at the last second resulting in the chakra scalpel cutting through his veins on his arm. He started to retreat and reanalyze the situation. Riku realized he needed to continue to pay attention. He needed to be more aware this person had around 9 years of experience on him he needed to realize that his sever release wasn't so strong that it could cut through anything he wasn't at that point yet and to get there it was incredibly hard. But he noticed that Kabuto had to misdirect his blade being in capable of deflecting the sever release or blocking it. He also needed to finish Kabuto in one hit as well because he was a medical nin he could heal himself while they are in combat it was different then what Riku did in the forest of death because Riku would need to fully concentrate on his wounds while Kabuto who was trained to be a medical nin could multi task it easily as it was a big part of their training.
Riku was composing himself and soon taunted Kabuto to come at him. Kabuto did so as he rushed to Riku and thrusted with his right hand at Riku's chest which Riku dodged to the right of Kabuto to get to his back side and he slashed at Kabuto's back leaving a good cut. Kabuto shortly after recovered and swiped his left hand at Riku's chest but Riku thought that he fully dodge. Riku started to feel pain in his chest as he realized he didn't dodge the attack he was hit in the chest but this time it wasn't only an internal injury this time he bleed from his chest luckily it wasn't a deep wound so he could still fight. But now he was on a time limit the wound wasn't deep but it was big enough where he could die from blood loss in addition to the internal bleeding from his arm from earlier.
Riku now rushed to Kabuto and realized he closed his wounds again making his time of fighting longer then Riku's. Once he got to Kabuto he was slicing again but as he was getting weaker from the blood loss his hits were a lot easier to misdirect as well as soon his chakra was weakening from him being injured Kabuto was deflecting and blocking. Riku was trying to keep his distance as well as he had the range distance while Kabuto had the advantage of having two weapons instead of one. But as the fight was going on all that was happening was Kabuto sustaining minimal damage and stopping the bleeding of his injuries while Riku only kept losing time. Riku was hitting his limit when a voice shouted at Riku like he was an idiot and he realized that the voice was Ryu.
Ryu: Hey kid are you stupid? Taking all this damage and not using one of your trump cards. What is the point of training them if you don't use it. Look I understand that you don't want to show it till later but you have so many up your sleeve you might as well win first with it instead of just having a 50/50 chance of losing. Plus it would help you improve your trump cards.
Hearing this Riku did feel kind of dumb as he should have used one of his trump cards when he realized that Kabuto could misdirect his attacks. So what he did was he summoned one of his sheathes from his storage cloth that was hanging on his waist. He quickly inserted Asami into the sheath and transferred the stored unicorn chakra from the sheath to his blade and fused the energies again just like his fight against Haku. As he fused them he rushed towards Kabuto and took his sword out of the sheath and attack Kabuto.
Riku: Secret Technique: Severing Spirit Horn Slash
The next second he was able to cut through the chakra scalpel and as he was about to hit Kabuto he let the chakra unfuse releasing a big impact of chakra as he sliced at Kabuto. Kabuto was blown back from the impact and hit his head against the wall leaving him unconscious and there was a wound on his chest showing the markings of a slash and the impact of the chakra. This was a hit that could of killed Kabuto but luckily Riku was so weak that it didn't have the force that the one that he used against Haku did.
Seeing that his opponent was unable to battle anymore Hayate said that Riku was the winner. Leaving many of the people in the arena stunned by the attack that Riku just performed. Many of the other participants realized that the attack was so strong that they wouldn't have been able to stop the attack. Many of the other sensei's just looked at Ryu wondering what he did to raise such a monster.
Guy: What is your student?
Kakashi: What was that attack and why have I felt the chakra before?
Ryu: Guy my student is just a kid just like your student the only difference is he is from special clans and has a knack for swordsmanship. Kakashi that was the attack that Riku used in your mission in the land of waves to beat that Haku kid.
Kakashi: Oh that is why it felt so familiar yet I didn't recognize it as I was so focused on Zabuza who covered our fight in the mist. But where did he learn that from?
Ryu: He said that he had a teacher that helped him create it. But sadly I can't tell you more you need to get permission from the kid for more info as he is very secretive. Now if you will excuse me I need to take this reckless kid to the hospital or he will die from blood loss.
Ryu went to the first floor and picked up Riku who was now lying on the ground after he won. He started to head to the hospital with Riku as they had a conversation.
Ryu: Hey kid you alright?
Riku: Yes I think. Thanks for the advice.
Ryu: Hey that's what I am here for.