His Media Graffiti series also continues, with magazine page doodles evolving over time to now include larger printed media such as Japanese subway posters. Mace annually produces New Year Card designs which adhere to the cycle of animals celebrated in the Chinese calendar. Mace used his Invisible Ink exhibition (2015, Tokyo) to formally introduce his "dry pen" technique. He had been employing the technique in some manner for some time, using "empty" ballpoint pens to draw invisible patterns, images and text into paper. No colors are added to some of these artworks; the imagery can only be seen when lit from an angle. To others, as in ¥ € $ (pictured), Mace applies ballpoint ink using his fingertips, exposing content previously drawn with a dry pen. Media in Japan and America in late-2015 began reporting about Mace building a "castle" in the Japanese Alps. Style Lennie Mace has been noted for his attention to detail; "intricately rendered" drawings showing "precision linework." He explains his ballpoint technique as "layers of overlapping lines" dependent of "pressure on the pen and texture of the paper," working with several colors simultaneously to achieve desired effects. Mace has described his own work as "non-political" and "self-indulgent," but content of a surreal nature — animal legs substituted by elaborately "carved" piano legs, for example — has led some reviewers to read symbolism into his work. Size varies greatly, from elaborate large-scale to simpler, smaller works. Mace has often incorporated materials reflecting the same "proletarian" origins of his ballpoint pens; office supplies and stationery such as loose leaf paper, corporate letterheads or memo pads, and post-it notes have all been utilized. This, he has explained, is in line with the "doodle"-like aspects commonly associated with these materials. Media reception New York Press supported Lennie Mace's early exhibitions by promoting his "superfine, surrealistic, and elegant" ballpoint artwork. Writer and performer David Aaron Clark, a fellow Screw magazine alumni and sometime collaborator, also promoted Mace's early exhibitions in previews describing "giddy, sleek masterpieces of fantasy and sensuality." Mace has professed to a "something for everyone" approach to filling exhibitions with whatever artwork is available at the time, including random sketch work, which has spurred criticism. The same critics, however, favored him as "a draftsman of almost infinite talent." He has also been called a master of ballpoint pen artwork, and his 2012 "Pen Pal" exhibition in San Francisco was