Information on the biology and appearance of Vash the Stampede in Trigun Stampede (2023).
Basic Physiology | Bounty | Clothing | Drain Gate | Earring | Energy Bullets | Energy Cube | Glasses | Gun and Marksmanship | Hair | Music | Personality | Plant Communication and Healing | Plant Lines | Plant Wing and Flight | Portal Gate | Prosthetic Angel Arm | Prosthetic Arm | Relationships | Roots and Flowers | Scars, Amputation, and Healing | Strength and Agility | Toma Equestrianism
After Knives penetrates Vash’s back with his knife tentacles in “To A New World“, he makes his “initial connection” with Vash. This triggers the release of a mass of dark, plant-like roots from Vash’s back, presumably from a gate point on his back that mirrors the gate point Knives uses to create the knife tentacles.
Knives appears to be able to control this first mass of roots, directing them to penetrate the dependent plants around them in the tank. When the roots connect, the dependent plants flash magenta around the root.
As Knives delves into Vash’s memories, blue pulses of light flash along the roots, leading from Vash to the dependent plants.
As Knives moves deep into Vash’s memories, manipulating away everything from after The Big Fall and reaching 87% sync, a second mass of roots begins to grow from Vash’s ankles and feet. These roots grow down and then out from the bottom of the tank, spreading into the observation area and then beyond it.
Conrad asks Knives if he is controlling the second mass of roots. Knives simply assures him everything is fine, and resumes his takeover of Vash’s mind, telling him to release his power. It’s unclear if Knives is in control of the second mass of roots, or if it is some instinctive, unconscious act on Vash’s part, or a combination of the two.
The roots grow with incredible speed, and even while Knives’ efforts stall, the roots have grown to completely cover the lab and spread out and down into the city below.
After Vash’s portal gate opens, flowers appear on the roots and bloom open. The flowers are purple geraniums with glowing blue stamens. The purple petals are dotted with blue specks like a starry night sky. These directly relate to the red geraniums that Vash associates with Rem, and which symbolize his memories.
With the portal to the higher dimension open, Vash’s roots grow enormous and spread over JuLai, crushing everything and everyone in their path.
This leads to the formation of a giant root monster in the shape of Rem that completely covers JuLai.
In “High Noon At July“, when Vash begins to recover his memories, a red light appears over his heart. A matching red light appears over the heart of the Rem root monster.
Retraction and Crystallization
After Vash awakens, he pulls his roots back, retracting them completely. According to Conrad, Vash refines the mass on a molecular level, breaks it into countless particles, smaller than air, and crystallizes it. The result is the Energy Cube.