This is the concept art. It was first hand drawn and then outlined and final design in Adobe Software.
Basically, the concept came from the skull in the design. I have seen many skull designs and lots of skull candies(my own version lol). But I wanted to mix the skull, the rope and the roots which resembles a tree. So I add the tree like branch in the head of the skull and also added kinda strong rope wrapping the skull. And you can see the final design. This is just a concept art and nothing in personal :). Check out more detail work below.