Skull tattoos are everywhere, they may very well be the most popular type of tattoos in the world. While we love realistic looking skulls, there's something about an artist taking artistic libertie.
masonic symbols - Google Search
The Ouroboros is a symbol that, as Carl Jung said, has great significance in the human psyche.
Masonic family map. More
LUX EX TENEBRIS (links to history of Masonic tracing boards)