At a cafe, Ral informs Sei and Reiji that the interference in their race was caused by a Gunpla mafia guy known as C. Reiji asks who they are, and Ral explains that they do dirty jobs for money, so someone is after them. Sei recalls the Mega Size Zaku attacking them earlier and wonders why someone would target them if they haven’t done anything wrong. Ral mentions hearing that the Zaku was sent in to spice up the battle, and Reiji abruptly excuses himself. He later storms into Mashita’s room after beating up his guards. He grabs Mashita by the neck and demands to know if he’s been interfering with their matches. Mashita sees the gem on Reiji’s bracelet and realizes that he is indeed the crown prince of Arian. Mashita tries to cover up and claim that he isn’t directly involved with the tournament. He promises to look into the problem and apologizes to Reiji, who lets him go. Reiji says he doesn’t care because he’ll accept any challenge, but he won’t show mercy to those who mess with the people putting all their effort into the tournament. Sei works on the Star Build Strike in the room and thinks about how they have to win tomorrow to get into the finals. Mashita tells Baker that he’s scared of his secret and the secret of the Plavsky particle being discovered, but she stops him when she hears a noise. Outside, Nils hangs over the wall and confirms that there is indeed a secret to the Plavsky particle. The next day, Allan tells Yuuki that the final qualifier will be one-on-one battles, so he’ll be fighting Khalifa from Oman. Sei and Reiji check the fight board and see that Fellini is their next opponent. Mao mentions what’ll happen if they lose, but Reiji insists that they’ll win. As the battles begin, Luang’s Abigorbine destroys an Alvaaron while Nils’ Sengoku Astray slices apart a Psycho Gundam. Mao’s Gundam X Maoh destroys a Zanneck, and Yuuki’s Kampfer Amazing defeats a Legend Gundam. Reiji joins China and Ral in watching the battles and is pleased that Luang made it to the finals. China asks where Sei is, and Reiji explains that he’s working on the Gunpla in deep concentration. Fellini runs into Kirara at a restaurant and doesn’t recognize her as Mihoshi. She’s impressed that Fellini has already made it into the finals before the last period, which means he can lose to Sei and Reiji so they can go to the finals. Fellini laughs it off as a joke, and later he thinks to himself that part of him wants to let them win, but that’s not his style.
A Geara Doga launches funnels, but it gets taken down by Aila’s Qubeley Papillon. She sees Sei and Reiji walk by, but they don’t recognize her under the pilot suit. Aila wants to watch the battle, and Barthes notes that it’s rare for her to want to do that. The battle begins in a canyon stage, with Fellini hesitating to fire to avoid the absorb shield. The Wing Gundam Fenice head butts the Star Build Strike, and Reiji opens fire. Fellini maneuvers to attack from behind and fires off center so that Reiji can’t use the absorb shield. He attack again and destroys the shield, leading Kirara to wonder why he isn’t trying to lose. Reiji tries to cut into the Wing Gundam Fenice’s left arm, but Fellini pushes him away and uses his vulcans to damage the Universe Booster. Mao comments that the Star Build Strike is losing, and Nils notes that Fellini is more experienced. However, Ral thinks that Sei’s knowledge of Gundam will help make up for Reiji’s inexperience. Inside the canyon, Reiji rigs a tripwire to the Universe Booster to distract Fellini and destroy his rifle. Fellini counters by destroying Reiji’s rifle and slamming into the Star Build Strike. Fellini apologizes for damaging his Gunpla and recalls being a young man and using a stock Wing Gundam that he slowly upgraded into the Fenice. Sei tells Reiji to use the RG system on full mode and says that Fellini intends to win at all costs, so they have to have the same resolve. Reiji rushes toward Fellini and maneuvers behind him to attack with a beam saber. The two attack each other with beam sabers and cause serious damage. Reiji uses an RG-enhanced punch, and Nils wonders why Fellini is fighting so hard when he’s already in the finals. Yuuki notes that Nils doesn’t seem to like Gunpla and suggests that he watch closely. Reiji and Fellini behead each other’s units and punch each other, damaging both units further. As a result, the battle ends in a draw, meaning that Sei and Reiji can advance to the finals. Mashita panics at the news that Sei and Reiji won. In the hotel room, Sei and Fellini immediately get to work on repairing their Gundams. Reiji eats snacks and asks if building Gunpla is really that fun, to which they both answer that it is.
The qualifying portion of the tournament ends with the most thrilling battle in the series to date. Prior to that, the best battle had been the one between Yuuki and Reiji before Yuuki took on the mantle of Kawaguchi. However, that was a battle simply for the sake of fighting with no grander stakes. Here, Sei and Reiji’s fortunes are on the line because they need to win to advance to the finals. Fellini wants to give them the full fight they deserve and pulls no punches, which leads to both Gundams being heavily damaged in an all-out brawl. It was surprisingly astute of Kirara to note that Fellini was thinking of losing since he likes Sei and Reiji and was already assured entry to the finals. In a separate subplot, we see that ninja Nils is spying on Mashita and knows that a secret is being kept. Following the confrontation with Reiji, it’ll be interesting to see how much more Mashita tries to make him lose.