

He used Autodesk AliasStudio and a Wacom Cintiq 21 UX tablet.
The final result is very good (even if some proportions are forced a bit), composition, colors, contrast, drama and energy are there.
To find the all tutorial go to: http://aliasdesign.autodesk.com/learning/tutorials/details/Digital%20Painting_133056/
I hope, as Kyle Rounciman says, that it might be of help to someone...have fun!
Photos and tutorial by Kyle Rounciman via Aliasdesign.autodesk.com