Martheus has illustrated for Bloodstream for Image Comics, Shooting Star Comics, Chaos Campus for Approbation Comics and Andrew Dabb’s Slices just to name a few. Recently, he has worked on such titles as Action Man for Hasbro, the Marvel Comics Masterpiece Card Series, and illustrated, wrote, and produced a comic book crossover called Jetta/Shi: Arrow of Destiny with his character Jetta, and William Tucci’s Shi. His work has been used for the movie Role Models from Universal Pictures as well as for the instructional DVD and book, Hi-Fi Digital Color for Comics II available from IMPACT Publishing. His work can be seen in Titanium Rain from Archaia Studio as well as Star Wars Galaxy Sketch Cards series 5. He has contributed to the Nanovor graphic novel from IDW Publishing as well as the popular manga series Mail Order Ninja by Josh Elder. His creator owned graphic novels Jetta: Tales of the Toshigawa and Turra: Gun Angel has been licensed for motion picture and his newest comic book, Shinobi: Ninja Princess, has been published by Action Lab Entertainment and distributed by Scholastic Books with a hardcover collection making its way to stores and libraries in 2019.