For the last level, you align the three bars to make a triangle in the center to generate a spike. The belts move according to the player's position. (There is a little bit of give in the alignment so you don't have to be spot on)

I can totally get why it was hard to understand. It was already kind of a weird design, and it was not polished out properly. The bars are a bit tilted and don't fully align. They also feel like platforms.

This level was the reason I decided to submit early. I felt this level idea was a bit weird and hard to understand. And the other ideas I had at that time were just getting weirder. So I decided to be okay with what I already have and upload it.