This is actually a basic Level 3 move. Once you learn how to invert, hanging on by your feet seems like second nature. I can actually hold this pose for almost a minute, and I'm working on holding it for longer by watching TV while I hold it, and trying to forget the pulse throbbing in my ears!
Its a little crooked in this picture because I have mild scoliosis, so forgive the asymmetry.
Inverted Crucifix