From Wikipedia, the free encyclopedia. Mark Sean O'Hare (born July 18, 1968) is an American cartoonist, animator, writer and storyboard artist who created the comic strip Citizen Dog. O'Hare is well known for his work on animated television shows as a writer and storyboard artist for Rocko's Modern Life, SpongeBob SquarePants, Dexter's Laboratory, The Powerpuff Girls, Hey Arnold!, The Angry Beavers, The Mighty B!, Chowder, and The Ren and Stimpy Show. Throughout the run of the series, O'Hare served as the creative director and supervising producer on Camp Lazlo. In 2016 he was employed as a storyboard artist for Illumination Entertainment. O'Hare has been nominated four times for an Emmy from the Academy of Television Arts & Sciences and won his first Emmy in 2007 for "Outstanding Animated Program" on Camp Lazlo and his second in 2008. O'Hare was initially enrolled in the aeronautical engineering program at Purdue University; however, after his sophomore year, he shifted focus to study graphic design upon illustrating a comic strip titled Art Gallery for the student newspaper, The Exponent. The comic ran from the autumn of 1987 to the spring of 1990. Afterward, he was accepted into the character animation program at California Institute of the Arts. He is a close affiliate of fellow director Tim Hill.