What is the Reason for Fighting? (戦う理由って、なに？, Tatakau riyū tte, nani?) is the second episode of the SSSS.Dynazenon series.
Monster of the week: Greyjhom (グレージョム, Gurējomu)
Yomogi and Yume visit the city where they fought the Kaiju and witness the tragedy. He and the others start their Dynazenon maneuver training, but a Kaiju appears again without any delay.
The episode begins with few moments leading to the conclusion of the fight against the gravity-controlling kaiju through Yomogi's perspective. As the young man braces for the worst as with the others, holographic word appears before him as with in Gauma's cockpit before Dynazenon splits apart before reassembling into its Dyna Rex form before finishing their opponent off, much to his awe before checking on Yume.
Meanwhile, Chise rushes for Dyna Rex as it descends before being distracted by a peculiar-looking pebble, though not for long until it disappears due to shrunk back to its components' toy forms.
Thanking his new co-pilots, Gauma informs Yomogi, Yume, and Koyomi that Dynazenon chose them because of their aptitude. Just as the worried Chise arrives at the scene, Gauma quick to remember the previous issue thus demands Yume to apologize to Yomogi, though Yomogi says it's no longer matter by that point. After the teens properly introduce themselves upon the salmon-haired newcomer, Gauma informs them that the kaiju they just destroyed was deployed by a terroristic crew of kaiju users like him and that his new co-pilots must prepare by mastering their respective Dynazenon's component vehicles starting from the next day since their enemies will commence another attack, an idea Yomogi skeptical of. While Gauma mulls over the reason of him being entrusted with Dynazenon, Yomogi recalls on what Gauma told him about Yume as he and the latter parted ways before noticing the ankhs on her hands.
On the next day, the fight between Dynazenon and the gravity-controlling kaiju has become a hot topic in public media as revealed by Nazumi who shows his friends a footage of the fight through his phone. Just then, the teacher informs her students that their classes will begin with 3rd period and their school will be delayed until third period in the light the kaiju attack, much to everyone's shock and Yume's indifference.
At their residence, Chise asks Koyomi whether she can join him and others' Dynazenon training. Koyomi says that she can before his mood improves upon hearing the prospect of getting paid for his troubles thus no longer a NEET.
Once the school ends, Yomogi declines his friends' offer to join them eating meat skewers together since he had a work to do. Yume parts way from Mei for her Dynazenon training with the latter taking a couple of pictures of her friend with her camera after they take their time playing together. Yomogi plans to do the same thing despite of it clashed with his part-time job schedule at Inamoto's store, though he eventually didn't. This of course, surprised Gauma because of the irony of Yume showed up when he least expected it at their meeting spot. And so, they had to begin without him.
Later that night, Yomogi is mulling over his potential as the pilot of Dynasoldier (Dynazenon's core robot) in his bathtub at his home until the naked Gauma unexpectedly joins him, much to his shock. As if that was surprising enough, his mother revealed to have let the friend he recently knows in straight away and even let him join them dining together. As much as he dislikes the idea of overstaying his welcome (he only visits Asanaka residence to confront Yomogi over his absence thus learning the latter's full-time job after school in addition of workaholic side stemmed from the fact that he already reached legal age quite recently in the process), Gauma accepts Mrs. Asanaka's offer to let him stay for the night nonetheless. Even so, he opted to leave at early morning out of respect, which is a good thing considering Yomogi barely able to sleep due to his loud snoring.
On the next day after the school, Yume meets up with Yomogi to bring him somewhere and show him what she learnt so far with her Dynawing (fighter jet component of Dynazenon). Transforming Dynawing into its true aircraft form via. its transformation call (Access Mode: Dynawing), Yume implores Yomogi to do the same with his Dynasoldier. Shortly after the young man transformed Dynasoldier into its true robot form with his own transformation call (Access Mode: Dynasoldier), Yume combines her Dynawing with the former's core robot of Dynazenon as sort of winged jetpack-like attachment. As they fly for their destination, Yume sincerely apologizes to Yomogi for breaking the promise they made on the other day, but Yomogi reassures her that he has gotten over it. Arriving at their destination which turned out to be the destroyed area of their home city with rescue teams still looking for survivors, Yume states that the situation would be much worse had they and the others didn't stop the kaiju. As they explore the ruined parts of their city, Yomogi wonders whether the responsibility to protect future attacks should be handled by someone else, but Yume argues that one cannot protect things they cherish at its fullest if their method is by-the-book.
Returning home with a train, Yume begins to open up more about herself; she lost her older sister in an accident when she was in elementary school right near the flood gate she (Yume) hanged out at on the other day. Their conversation that afternoon made Yomogi begins to consider about his newfound role once Yume informs him about their next training, in which he initially considers to pass for his current job at Inamoto's store.
At the group's next meeting spot, Gauma is mildly surprised by Koyomi's progress with his Dynastriker (racer car component of Dynazenon) before being dismayed by Yomogi's second absence as reported by Yume. Meanwhile, the city's citizens are surrounding the seemingly inert turquoise, pink, and purple kaiju, unaware that it was deployed by the arrived Kaiju Eugenicists; Juuga, Onija, Mujina, and Sizumu. Using Instance Domination, Juuga awakens the inert kaiju, causing it to enlarge and continue what the previous one started – sending the world into their knees. It doesn't take long for Chise to learn about the next threat via. mass media and subsequently inform Gauma about it, leading the gang to frantically look for the missing Yomogi until they managed to find the latter while still on his way for Inamoto's store.
Kaiju Eugenicists' next attack force begins its rampage before being intercepted by Dynazenon as Juuga expected, but they are better prepared than the last time; their current kaiju possesses the ability to teleport in order to overwhelm the mech as noted by Koyomi. To even their odds, the group splits into their respective Dynazenon vehicle component, a decision that dismayed Yomogi as he has yet to familiarize himself with his Dynasoldier unlike his friends. To compound the issue, he unexpectedly phoned by Inamoto due to his absence in her store. In his despair over the prospect of becoming a burden, Koyomi informs him that their opponent has the habit of spreading its wings whenever it is about to teleport before Yume suggests to use the combination from earlier. With their Dynazenon component combination properly named (Dynasoldier Wing Combine), Yomogi, now having a conviction as a protector as much as the others, has Dynasoldier tackling the kaiju all while keeping its wings in place with Yume bringing them both to the sky, further shocking Juuga and Onija as neither of them saw that coming. Tossing the-then vulnerable kaiju to the sky, Yomogi and Yume lets Gauma finish it off with Dynadiver's Dynalauncher: Burst Missile, blowing it into pieces.
In the aftermath of the battle, Gauma praises the group for their success with the relieved Yomogi sees the bus that caught in their fight moved on unharmed despite his own shortcoming. Yomogi then asks Yume whether she genuinely close to her late sister back then. Yume states that they weren't that close, but now she's unsure about it. The episode ends with victorious Dynazenon pilots come face-to-face with Kaiju Eugenicists at last...
- "Hands", the Ultraman R/B opening theme plays during Koyomi and Chis's conversation scene in their room.
- The episode reveals that Dynazenon was entrusted by a mysterious individual Gauma knows.
- 2.2: I grew up in a kind home (優しい家で育ったから, Yasashī ie de sodattakara)
- Yomogi and Gauma talk about Yomogi's family and why he wants to be independent.