 Clarke was one of the artists who took up the slack after original editor Harvey Kurtzman left "MAD", taking two of its three primary artists (Will Elder and Jack Davis) with him.In his first year at "MAD", Clarke illustrated 24 separate articles; he would eventually draw more than 600.Clarke was a mainstay of the magazine as it rose in circulation, being one of four general-purpose artists who took "MAD" through the late 1950s and earliest 1960s, the others being Wallace Wood, George Woodbridge and Joe Orlando (Jack Rickard's work appeared in mid-1961, while Don Martin, Mort Drucker and Dave Berg produced more specialized topics or features).