#Also I'm very much so a surface level quantum physics nerd I am NOT an expert

[revenantghost]

can you explain why knives needed vash for his plan? is vash's power giving plants life?

So from what I gather, Vash is unique in his ability to both give and take from the higher dimension, which is the place where all plants get their energy from, and that's what humans use them for. (This is also where Conrad says their souls are instead of their bodies (possible bullshit, given the unreliable narrators we have), and also given Vash's conversation with Rem in episode 12 it's possibly connected to the afterlife???) Or, at the very least, Vash is different from most other plants, as they can only take. His power has been compared to something black hole-like, but I won't bore you with quantum physics since we don't know exactly what they mean by that yet, exactly.

In order to access and enter the higher dimension to rip souls free and shove them into the plants' bodies to birth independent plants, Knives needed to use Vash as a gate, as a tool, to open Vash up and let himself in so he could funnel that power out through Vash.

At least, that's just what I've gathered from watching Tristamp... way too many times and reading meta as I go. I'm probably a bit off in this explanation, so anyone feel free to add on anything I missed! I think we're going to get way more in-depth in the following season/s with the plot threads left hanging after episode twelve. Hopefully this makes sense! :'D