Satoshi Mizukami/Plot

Background
Mizukami hails from Ōsaka. As a child, he was a prodigy at shōgi and was on track to become a professional player until middle school. He was eventually scouted by Border.

Introduction Arc
Ikoma Unit presumably takes part in the extermination of all Rads in Mikado City.

Large-Scale Invasion Arc
Ikoma Unit is seemingly not deployed during the Second Large-Scale Invasion, and could, therefore, be among the B-rank units with missing members which Masafumi Shinoda prevents from fighting against Aftokrator's forces out of fear of capture.

Round Two
On February 5, Ikoma Unit faces off against Ninomiya Unit in the second round of rank battles. Since Azuma Unit, Katori Unit, Ōji Unit and Yuba Unit compete in a four-way match in the day division, it can be inferred that the three-way battle takes place in the night division and that Kageura Unit is the third participant.

Round Four
Since Tamakoma Second fights Ninomiya Unit, Kageura Unit and Azuma Unit in the night division of rank battles on February 15, and since Katori Unit and all other possible opponents were in the middle tier of B-rank or lower, Ikoma Unit must have fought in the day division against Ōji Unit and Yuba Unit. After the scores from both divisions are tallied, Ikoma Unit remains in third place.

Galopoula's Blitz
Since Azuma Unit, Kageura Unit, and Yuba Unit fight in the night division of rank battles on February 19, Ikoma Unit must have competed in the day division against Ninomiya Unit, Ōji Unit and Suzunari First. They rank third at the end of the match. That same night, Ōji Unit and Ikoma Unit are deployed to intercept opponents west and south of the base in preparation of Galopoula's incursion.

Round Five (Night)
After the results of both the day and night divisions are tallied in round five, Ikoma Unit ranks third, with 27 points.

Round Six
Ikoma Unit is pitted against Ōji Unit and Tamakoma Second in round six. On the day of the match, the team members are gathered in the strategy room, discussing Tamakoma Second's prowess. Mizukami is particularly worried by the wire strategy. After Kōji Oki points out that Maori Hosoi seems to resent not being complimented, Mizukami joins Tatsuhito Ikoma and Kai Minamisawa in singing her praise. He then reviews how they can counter Chika Amatori's Lead Bullet, and tasks Oki with taking her out. The conversation moves to the menu of the cafeteria until the start of the match.

Mizukami spawns in the western portion of Cityscape A and quickly meets up with his captain. When Yutaka Kashio dons a Bagworm, Mizukami surmises that he must be looking for Chika or Osamu Mikumo, who is also off-Radar, so he warns Minamisawa about the possibility of a sneak attack. As Minamisawa engages Kashio, Ikoma and Mizukami start heading towards him, but he bails out before they can reach him. Ikoma launches his signature Senkū attack, which all of Ōji Unit and Yūma Kuga survive. Mizukami thinks it a fluke and tells him to try again, but they all dodge again and Yūma escapes. At Ikoma's behest, Mizukami targets Kazuki Kurauchi with a Hound volley disguised as Asteroid, although Kazuaki Ōji sees through his deception and warns his teammate in time. The Shooter is however beheaded by Yūma with a sneak attack, so Ikoma and Mizukami shift their attention to Yūma. When Chika takes a shot at them, they pressure Oki into making more of an effort.

It is not long before the Sniper is found by Ōji, so Ikoma and Mizukami make their way towards him while fighting Yūma. As both the Tamakoma Second ace and Chika reach the wire zone, she proceeds to raze the buildings around Ikoma and Mizukami, who follow their target into their turf. Mizukami recommends attacking from a distance as they cut down the wires until Oki snipes Chika. However, he is hit by her Lead Bullet when Yūma stuns him with a piece of debris, and immediately beheaded by Ōji's sneak attack. The match terminates not long afterwards, with Ikoma Unit and Ōji Unit scoring three points against Tamakoma Second's four. After the results from both the day and night division are tallied, Ikoma Unit remains in third place with a point total of 34.

Round Seven
Since Tamakoma Second faces off against Kageura Unit, Azuma Unit, and Suzunari First in the day division of rank battles on March 1, it can be inferred that Ikoma Unit competes against Ōji Unit and Ninomiya Unit in the night division. After the results of both the day and night divisions are tallied, Ikoma Unit ranks fourth.

Round Eight
On March 5, Ikoma Unit is pitted against the Ninomiya Unit, Tamakoma Second, and Yuba Unit in the night division of rank battles. The fighters are as relaxed as ever, listening to Ikoma's rambling stories. Mizukami spawns in the center-northern area of Cityscape B. As he begins to move eastward, his attention is soon caught by a bombardment in the west, which he supposes to be Masataka Ninomiya's doing. The trion signature on which members of multiple teams converge disappears, but Oki is able to spot its owner, Hyuse, and they decide to target him. As Takuma Yuba, Yukari Obishima and Sumiharu Inukai also join the fray, Mizukami monitors the fight while keeping Hyuse penned in. He is briefly distracted by a massive explosion caused by Chika's Meteor misfiring. Hyuse manages to hold off the close-ranged fighters, but Inukai and Mizukami stop him in his tracks as he attempts to flee. Mizukami is surprised by Hyuse's presumed Asteroid turning out to be Viper and forcing Ikoma to bail out. The remaining bullets turn towards Minamisawa, but Mizukami shields him, so he is able to deliver the final blow. As Hyuse bails out, Mizukami finds himself pincered by Yuba and Inukai. Unable to guard against both their attacks, he is defeated by the enemy captain. When Oki snipes Kazuto Tonooka, Mizukami protests that he could have used his skill to help them, but the Sniper replies that everyone else was ready to defend.

The match ends with Ikoma Unit and Yuba Unit tied in third place, having scored two points each. When the final commentary does not answer his questions about Hyuse's ability to dodge his first Senkū, Ikoma turns to Mizukami, who explains that their movements confirmed that their movements and numbers tipped him off. The season of rank battles ends with Ikoma Unit ranking fourth, with a total of 34 points.