Muten Roshi, Karin-sama, Bulma, and Chichi fly toward the battle field where the fight with Vegeta is drawing to its conclusion. Using his powers of ki detection, Karin navigates across the skies. Muten Roshi is privately troubled. Five presences he cannot sense... Tenshinhan, Yamcha, Chaozu, Piccolo, and Goku.
Chichi is more concerned about Gohan.
(Gurl, you dancing with the devil now.)
Gohan's tail has regrown, as Goku's did when he was a child. (I wonder if Saiyan children regrow their tails during a time of stress? Given how Goku regrows his during the 21st Tenka-ichi Budokai.) With Vegeta's artificial moon in the sky, he fears the repercussions if Gohan managed to see it and transform into an Oozaru. As such, he resolves to remove his tail, eliminating the problem.
But he didn't count on Yajirobe.
"Not in my house, bitch!"
Well, it was a good try anyway, bro.
But as Vegeta is distracted by Yajirobe, Goku uses telepathy to speak to his fallen son. He urges Gohan to look at the ball of light in the sky, realizing they have but one chance for victory.
Kuririn isn't pleased to see another Oozaru, remarking how Goku lost all his reason when he transformed. As Gohan smashes up the mountains surrounding them, it becomes plain that he, too, loses himself to his transformation. Kuririn assumes that it is because they revert back to their Saiyan instincts. Goku telepathically shouts for Gohan, which stuns the beast, and Kuririn pleads for him to go after Vegeta... and miraculously, he does it...!!
Vegeta is utterly beaten. Still alive, though barely just, he calls for his space pod. Kaio-sama watches the fight ending, remarking how it is good that Vegeta has lost, but that the root cause of the evil still remains. (FORESHADOWING, DUN DUN DUUUUUNNNN.)
"It's called a spoiler alert, you prick!"
As Vegeta crawls, broken, to his space pod, bitterly cursing his defeat at the hands of scum, Kuririn takes up Yajirobe's katana to finish the job...
But before he can, Goku telepathically shouts for him to stop. And he asks Kuririn to let Vegeta go.
"Please... This is the only thing I'll ever ask of myself..."
Kuririn doesn't want to do it. Vegeta isn't Piccolo. He won't have a change of heart. He killed their friends, and he'll return to kill them as soon as he recovers. But Goku understands that fine.
"I ain't able to say this too well... but when I saw him nearly dead there... I thought, "What a waste".
Goku wants to fight Vegeta again. He wants to surpass him, and properly. He thought Kaio-sama had taught him his limits, but Vegeta was far beyond them. His Saiyan blood urges him to go even further. And to do so, he needs Vegeta.
Reluctantly, Kuririn drops Yajirobe's katana.
And Vegeta smirks, taunting Kuririn before he leaves the Planet Earth.