Anyone simply ASTOUNDED by the narrative incompetence of this whole scene? First of all, if Oku couldn't have had the fight during the climactic tower battle, or maybe the circus battle, then he should have just pretended the alien war hero character never existed, or at least set up a finale scenario in which the war hero and his squad seize a ship, load it up with anti-matter bombs which would life-wipe the Earth:
https://youtu.be/NJ5_byx6Ues?si=v0h3cgFM_03iRZoR
THEN have Kuruno run off alone for a desperate, near-impossible mission to stop it. Have the rich fucks get their shit together one last time and work together with all their might to give Kurono a re-spawn cheat just as he gets splattered by an enemy vastly stronger than him. Even as he gets re-spawned, however, it causes psychological trauma and so the resolution stays poised on a knife's edge until the very last. As he gets surrounded by being outnumbered on top of being out-classed, suddenly re-reinforcements come in from Gantz. The rich fucks had put the call out to the public: if you want to save humanity, raise your hand. It's a one-way trip and you can't be resurrected because that has to be turned off for the re-spawn hack they're doing. People all over the world watching this impossible fight of despair suddenly start stepping up. One after the other regular civilians find their ballsacks for once their lives and raise their hands, trading their lives to give Kuruno a half a second of breathing time. Seeing this stream of literal whos show up to throw themselves at the aliens moves Kuruno emotionally and he overcomes the trauma.
AND EXPLAIN THE WAR HERO'S FEELINGS. This is an absolute staple of battle shounens, it is the one good trope from the genre. Show who the guy's weak little brother was everything to him, how the entire universe only mattered because lil bro was in it. it can be a standard emotional character development, but it MUST be there for this kind of fight.
