Crazy Speed Drawing: Metal Skull - 3D illusion

My first speed drawing on YouTube and also my first drawing after 20 years. Okay, it's not my best drawing, but I'm quite satisfied :) http://www.marcellobarenghi.com
➜ SUBSCRIBE YOUTUBE: http://www.youtube.com/user/marcellob...
➜ PLEASE TURN ON NOTIFICATIONS so you never miss a drawing :) info: https://support.google.com/youtube/an...
➜ FACEBOOK   / marcellobarenghi  
➜ INSTAGRAM   / marcellobarenghi  
➜ GOOGLE+ https://plus.google.com/+marcellobare...
➜ TWITTER   / barenghim  
➜ MY DRAWING TOOLS:
mixed media on grey paper, pencil 7B, 9B, B; white chalk pencil; smudge; black and white acrylic http://www.marcellobarenghi.com/p/mat...
➜ FINAL DRAWING: http://www.marcellobarenghi.com/2013/...
➜ THIS DRAWING TOOK ME: 1 hour
➜ MUSIC: created in GarageBand

Original title and notes (2013)
Crazy drawing illusion 3d - the metal skull HD video speed painting
I stopped drawing by hand in 1993, this is my first one after 20 years :)