When it comes to sheer output of work I think it would be hard pressed for many humorous illustrators/artists to rival Jack Davis. Jack Davis' art fit perfectly into MAD with its humorous slant and exaggerated motion it is no wonder that his work was so sought after. When Harvey Kurtsman left MAD to join Hugh Hefner and launch TRUMP Jack Davis was one of the artists that followed him. Similarly when that project died after only 2 issues Jack was one of a few that started HUMBUG which lasted 11 issues until late 1958. After that Jack started drawing for a myriad of publishers and their magazines from SICK to CRACKED to YAK YAK (which incidentally was written and illustrated by him). After much roaming Jack finally returned to MAD illustrating a piece on monsters in '69.
Above are just a few covers to some of these publications.