18. Phlegm

While he got a little less mysterious in 2012, Phlegm also became more prolific. Ireland, New York, Norway, Portugal, and his hometown of Sheffield, UK now boast new work by the steam punk influenced street artist. Some folks on the international mural scene survive on a few tricks, Phlegm manages to stay consistent in tone and varied in narrative. 

This video of Phlegm's work in Bantry, Ireland remains the best street art video of 2012.