A simple two part move, with an awesome effect if achieved. I mean, achieving it is a task of its own due to the gap between the knee and the elbow, but of achieved, the target is yours. They would be unconscious, so you could capture them, kill them, torture them, or whatever else you would like. It would be nice if the knee was taken out to turn this into a elbow shot to the back of the head, but that would be too easily abused, so I see why it is the way it is. I can see myself experimenting with this one, that effect is too good to ignore for now lol. Another cool thing about this technique is the way that it is worded, you know where the counter is coming from. Allowing the knee to go through would make your opponent bend at the waist. Either due to pain, or the forward motion of your knee compared to their stationary body, either way allowing it to go through almost ensures the next part happening, so they have to stop the knee to be completely safe.