Vash realizes the only way to stop Knives is to absorb the energy sphere himself. He fully unleashes his Plant form (white wings, geometric halo). The strain cracks his body. Knives screams that Vash is betraying their kind.
Vash successfully contains the blast but at the cost of July being partially vaporized (the crater is later called "July"). He collapses, reverting to human form, missing his left arm (blown off by the energy). Trigun Stampede -Dub- Episode 12
Knives activates his own full Plant power, creating a massive energy sphere over July City. Vash tries to contain it but loses control. Wolfwood shoots at Knives to distract him – it fails. Zazie (the giant worm) tries to help but is swatted away. Vash realizes the only way to stop Knives
Knives, wounded but alive, retreats with a mysterious figure (later hinted to be a human ally). Wolfwood finds Vash barely alive. Meryl holds Roberto’s body, then stands and takes Roberto’s broken camera – she will continue his work. Knives screams that Vash is betraying their kind
Meryl and Roberto are caught in the chaos. Roberto shields Meryl from debris, sustaining a fatal injury. He tells Meryl to "tell the story right" – a direct callback to his earlier cynicism about journalism. He dies.