A vertical kick aimed at the target's defense even when there is attacking and defending at the same time. The user goes through a 3-step of training to be able to use this technique.
- First Step - Balance: The user learns to stabilize their center of balance by running around the edge of a building, jumping up and landing on the bricks.
- Second Step - Power: The user stands in the distance and then focus all of the power into their feet to leap a long distance up to at least 5 meters. Once they master this, they have to try jumping across, landing on top of another building. After the user mastered the first 2 steps even when they fall, they can easily land on the ground without much difficulty by controlling their power and using their newfound mastery over their center of gravity.
- Third Step - Awareness: The user has to run through a group of people while staying in their "korui", their blind spots. The main goal of this exercise is to see the area in which the defense is the weakest.
Once the practitioner can see the Korui, he focuses all of his power while maintaining his center of balance and delivers a kick at the opponent's weak spot.
The only major weakness of this technique is that the user has to focus all their power into their legs, forcing them to lower their arms and enter a guardless stance. An enemy could easily land a devastating attack towards their upper body, such as when Ethan broke one of Kenichi's arms. This is, however, useful since they can lure their opponent closer and use the attack at point blank range.
Currently, since all of Kenichi's might is put behind the kick, this is one of his strongest techniques. According to the Ryōzanpaku masters, if Kenichi uses Korui Nuki correctly, then no one in the Three Disciple-class and the Expert class fighters are able to withstand it. The only people who has managed to stop this attack and counter it are Tirawit Kōkin and Kajima Satomi. In the former's case he managed divert some of the damage by kicking Kenichi in the back during the technique's execution while the latter managed to block it with pure strength alone which astonished Shigure Kosaka.