A Conscious Intersection 
I am one of many.
Description[]
A Conscious Intersection is a small sub-area only accessed after completing Surge's quest of bringing him 1 Dark Feather.
After completing the Quest, Surge starts acting weird, and when trying to return to the Widow's Den, you instead find yourself in a hellish glowing nightmare with The Nestmind at the end. This area is vital to obtaining the Visionshaper Oath.
It is theorized that this area is not actually inside of The Depths, and may be somewhere inbetween, hence the "Intersection" part. As for The Nestmind, this is probably not it's true form, much like how the Shrine of Yun'Shul isn't actually Yun’Shul, just a device to communicate safely with them.
Falling into the void takes you to Layer 2.