Koarai is known to be a child prodigy. Although he was noted to be an average fighter on his own, Okudera and he can coordinate so perfectly that they were said to be able to defeat most higher-ranking opponents by teaming up. This is especially remarkable given that Attackers have a harder time making the most of their numbers against a single target. According to Kazama, their teamwork at close quarters is second only to his own unit's. Their proficiency extends to aerial combat. Generally speaking, Okudera serves as the diversion and decoy and is responsible for engaging the opponent first due to his superior watchfulness, while Koarai deals the finishing blow. Nonetheless, he can be observant in the midst of combat, which he demonstrated when he guessed that Tsuji was about to attack from Inukai's movements. He also has decently quick reflexes, which allowed him to partly fend off a sudden attack from Mikumo accelerated with Thruster, dodge a Mantis strike from Kageura, and intercept a sneak attack from Tsuji, though, unlike the latter, he was unable to react to Kuga's follow-up.
Koarai is known to be a gambler in terms of planning, and he seems to specialize in spotting possible advantages, whereas Okudera focuses on the drawbacks. Under Azuma's tutelage, Koarai's eye for strategy is steadily improving and his analytical skills applied to the preparation phase of the battle have been refined between his unit's two fights against Tamakoma Second, although his enthusiasm and recklessness still need Okudera to be checked. After the unit's second match against Tamakoma Second, where Koarai was able to keep his hot-headedness in check and espouse caution, Azuma declared him mature enough to start adding Triggers to his Sub column, which he had previously forbidden him to do.
According to Sōya Kazama, Koarai is not particularly powerful on his own, and in fact he lost 5 matches out of 5 against Hyuse while both were using only Kogetsu. He was also surprised twice by sudden attacks from Osamu Mikumo, although on both occasions he managed to react quickly enough not to suffer any damage. However, his coordination with Okudera is such that together they can take down most higher-ranked opponents, their teamwork being second only to that of Kazama Unit. They demonstrated this by whittling down Master Class AttackerShinnosuke Tsuji, who was noted to be individually stronger than Koarai. Koarai is in charge of dealing the finishing strike after Okudera locks the opponent in place. Koarai is first seen using Kogetsu in chapter 44 (episode 22 in the anime).
Koarai uses Bagworm to target specific opponents without their knowledge until he launches a sneak attack, dispelling the Optional Trigger right afterwards, as well as to meet up with Okudera without being intercepted by enemies. On one occasion his unit had engineers change the color of their Bagworms to white so as to camouflage in a snowy map. Koarai is first seen using it in Chapter 110 (Episode 67 in the anime).
Koarai rarely utilizes this Trigger, seemingly preferring to close the distance with an opponent he is not at too much of a disadvantage against right away, especially if Okudera is around. However, he will resort to it to cut down an enemy who tries to escape by leaping. He was only seen performing a single slash with it. Koarai is first seen using Senkū in Chapter 172.
Although this Trigger is not part of Koarai's normal set, he often adds it to improve his mobility on certain maps while the terrain makes movement on foot unfavorable for his opponents. He can also use it to precede an enemy and trap them between himself and Okudera, or more generally to change direction in mid-air. Koarai is first seen using Grasshopper in Chapter 168 (Episode 68 in the anime).