Roots

This is a creepy and wonderful piece. Your description is perfect, it truly looks like "[a]n anatomy study run amok."

Firstly, the colors you use in this piece are perfect. They're dark, almost grim. You utilize the contrast between dark and light very well, giving it rich shadows, and lighter spots that draw the eye. The contrasts make it very visually appealing to the viewer.

Secondly, your lines have depth and clarity, as well as give a flow to your piece that keeps the eye moving, seeking out each detail, wanting to look at every portion of it.

Finally, the details are perfectly done. You put in some, but not too many. This gives the faces and the bodies entangled in the roots a more mysterious and dark air.

Overall, it's extremely well done.