A young Knives reminisces about when he was a child with Vash, playing their duet on his own in his room in what will become July. Conrad enters to tells Knives he's obtained something and to ask what Knives is up to, only for Knives to lift his head and frown angrily when they're interrupted by the blaring alarms, alerting of a failure in a Plant.
Knives and Conrad go to examine the Plants, which have all turned red. Knives sees his sisters withering away, pushed beyond their limits by human technicians to meet their demands. Knives orders Conrad to heal them, but there is nothing either of them can do. The technicians then force the Plants into a Last Run, pushing them even further to harvest their final burst of energy as they die. Outside, the city lights up. Knives falls to his knees, helplessly staring at the withered husks of the Plants.
Vash then appears and calls out to Knives, who stands up, removes his hood and looks at his brother. As the humans attempt to forcefully remove Knives from the scene, he snaps and slaughters them. As the surviving humans cower in terror and call for reinforcements, Knives announces to Vash that "Nai" is no longer his name, and that he has a plan to free their sisters using the power both he and Vash hold. He kills the remaining humans and Luida enters, asking Vash earnestly to come home with her.
Knives then picks up a gun and hands it to Vash, telling his brother to join him in his crusade to free their brethren, starting with his first casualty: Luida.
Tropes that appear in this episode:
- An Arm and a Leg: Vash's left arm gets sliced off by Knives, as he stops the gate that appeared from possibly consuming Vash.
- Armed Legs: Along with the claws on his hands, Knives can also create blades from his feet.
- Big Brother Instinct: Knives drops his attempts at killing Luida in favor of stopping Vash's gate arm from possibly killing his little brother.
- Blatant Lies: After calling Meryl by her name to find him a smoking area, Meryl gleefully runs over to Roberto and asks if he actually called her "Meryl" and not "newbie". He immediately denies this and after the two wake up from being kidnapped, he goes right back to calling her newbie.
- Crazy Jealous Guy: As he strangles her, Knives calls Luida a "witch" and asks how many times humans like her will "steal" Vash away from him.
- Curb-Stomp Battle: Knives carves through all of the humans in the vicinity, with none of them even able to get a shot off.
- Deadly Dust Storm: Averted. Luida and Brad use a dust storm to hide Ship Three when they travel around to avoid contact with the people of Noman's Land and keep a low profile.
- Earth That Was: Zazie confirms to Roberto and Meryl that the humans currently occupying Noman's Land came to this planet because they had already destroyed earth. Now Zazie wants to ask Meryl if humans will treat this planet any differently than their previous home.
- Extreme Close-Up: Zazie gets up close and personal with the camera asking for Meryl's answer on who should live amongst the Worms.
- Eye Scream: The first human Knives kills he stabs through the eyes with his claw.
- Friendship Denial: Wolfwood is the only one to reject Luida referring to him as one of Vash's friends.
- Genocide Dilemma: Zazie poses this question to Meryl as they explain Knives's plan to wipe out all humans. After revealing that the humans' original planet, Earth, was destroyed due to their own greed, would they act any differently on No Man's Land and use the Plants sustainably? Who would best serve the Worms, who have lived here since the beginning? Plants or humans?
- I Did What I Had to Do: The one human able to get some words out before Knives kills him says that the Last Run is something they need to to do so they can survive. They have to use more energy from the Plants to build enough to keep everyone else alive, but Knives only sees the abuse and eradication of his kind, and certainly not his own part to play in stranding humanity and the Plants in such conditions.
- Kick the Dog:
- When Dr. Conrad sharply upbraids the technicians for treating the Plants as though they're disposable, the lead Plant technician chuckles and says they were born to serve humans, and he's sure they were "just happy to be useful," then orders Knives restrained and removed from the area. It's not that surprising what happens to him afterwards.
- Knives may have gotten closer to convincing Vash to join him if he hadn't sneered at Rem's "meddling" for ruining his sabotage, viciously mocking Vash's obvious grief over her death.
- Leitmotif: The song that Knives has played since the first episode was one he and Vash created together as children. He's practiced enough that he can play the duet on his own, but still longs to have his brother play beside him once more.
- Life-or-Limb Decision: Knives slices off Vash's left arm, apparently the source of his Gate, to save his brother from being consumed by it — Vash was too shocked and confused to work out how to control it himself.
- Long-Lived: Luida and Brad reveal they've been with Vash for about one hundred and fifty years, periodically going into cryo-sleep to extend their lives a bit more and maintain the ship. This is also the first concrete confirmation of how old Vash truly is.
- Making the Choice for You: Knives tells Vash to join him by killing Luida. When Vash hesitates too long to make a decision, Knives takes the gun and prepares to shoot her himself. Vash finally steels himself and charges at Knives to stop him.
- Meaningful Rename: While Vash still calls him "Nai", Knives tells his brother his new name, Millions Knives, the name he gave himself to represent his mission to strike back for their suffering and dying sisters.
- Mirror Character: Conrad recognizes Luida; the two are both Plant specialists, community leaders (respectively of July and Home) and even surrogate parents to the twin they've met. But where Conrad experiments on the innocent for Knives's and his idea of humanity's "benefit", Luida is attempting to grow (normal, green) plants and flora, hoping to lessen the strain on their Plants.
- Mirthless Laughter: When Vash points a gun at Knives, Knives looks shocked and tries to cover it up by chuckling, but it's obviously only so he can keep from crying or screaming in front of his brother.
- Mugging the Monster: There are worse ideas than trying to restrain a lanky teenager, unless that teenager happens to be Millions Knives.
- Mythology Gag:
- Vash's gun in Stampede is of a different size and caliber than the gun of his previous counterparts, but it's shown in this episode that it originally was the same model as the gun of his previous incarnations, and that Vash must have modified it since. This also isn't the first time Meryl has been kidnapped by Zazie and used as bait to lure Vash in, which was something that happened in Maximum. In Stampede, however, luring Vash is incidental to Zazie's goal of learning Meryl's opinion on the conflict.
- In Maximum Luida asks Wolfwood to not smoke on the ship (even though he didn't have his cigarette lit), but in Stampede, she tells Roberto no smoking is allowed.
- Neck Lift: Teenage Knives easily lifts Luida up by the neck as he attempts to strangle her.
- No Smoking: Just as Roberto pulls out a cigarette to light after making a big speech, Luida calmly tells him smoking is not allowed on the ship. Roberto chokes on the smoke as he quickly tries to put it out.
- Pre Ass Kicking One Liner: Knives finally decides he's had enough and prepares to kill all of the humans in his sight. In Japanese he says, "Just let me hear your screams." In English, "I only want to hear your screams."
- Power of the Void: Vash's Gate finally activates on his left arm, revealed to be an ersatz black hole that consumes rather than a gateway that produces as Plants typically have. It starts dragging in everything in its surroundings, starting with the corpses of the humans Knives killed, and finishing with Vash's left arm after Knives slices it off, as Vash was too confused and frightened to figure out how to control it before it consumed him too.
- Skewed Priorities: Roberto's reaction to waking up after being kidnapped is joking glee that their new location probably isn't a No Smoking zone.
- We Can Rule Together: Knives's main pitch to Vash was how they can wipe out all of the humans on the planet, and start it anew together.
- Wild Card: Zazie apparently has no true alliances — kidnapping Meryl and Roberto was not an order, just something Zazie decided to do. They call themselves a "guest" of Knives and are willing to give Meryl some information and to hear her opinion on who would better serve the planet: humans or Plants?
- The Worm That Walks: Zazie reveals their current form is simply a vessel for the Worms, the true natives of No Man's Land. When Roberto fires on Zazie, the body simply dissolves into flying Worms before reforming.
