Shel Dorf, who founded the San Diego-based Comic-Con International comic book festival, died Tuesday at the age of 76 from kidney failure, reports Reuters. The freelance artist and comic strip letterer suffered from diabetes and had been hospitalized for most of the year. While the first convention in 1970 attracted about 300 people, it has grown into an international pop culture event that draws fans of practically all types of entertainment. Comic-Con 2009 was attended by more than 125,000 people.