<P> The series is rated TV - PG - V. Cartoon Network told Quintel early on that they wanted to "age it up from the TV - Y7 stuff we'd been doing in the past". This direction led the crew to use adult - oriented humor with innuendos and drug and alcohol references because they wanted to cater for both the younger and adult audiences . The writers generally make these jokes subtle . The show also makes use of sub-textual adult humor through music . One of the program's storyboard artists, Calvin Wong, said that he enjoys the limitations set by writing for the show since the adult - oriented jokes that are approved are satisfying . </P> <P> The plots of the episodes are influenced by the writers' and Quintel's personal experiences, such as performing prank telephone calls or accepting an eating challenge from a restaurant . The show often references 1980s culture, using music and electronic devices from that era because many factors from the decade left a positive influence on Quintel . The show also makes references to modern social trends such as viral internet videos . </P> <P> The voice acting of the series is relatively low - key, and the intention was to make most of the characters sound natural and conversational . Quintel wanted to make the show listenable and given contrast to most other cartoons, which often are difficult for adults to listen to . The main cast consists of voice acting veterans Mark Hamill, who portrays Skips and Roger Craig Smith, who plays Thomas . William Salyers plays the voice of Rigby, Janie Haddad portrays Margaret and Quintel's former CalArts classmate Sam Marin voices Benson, Pops, and Muscle Man . Quintel portrays Mordecai and Hi - Five Ghost . Members of the production staff have voiced several characters throughout the series; these include Minty Lewis, Toby Jones, Andress Salaff, and Matt Price . The Regular Show cast record their lines together in group as opposed to individual recording sessions for each actor; this is to help the show's dialogue sound natural . The series regularly uses guest voice actors for recurring characters; these guests include Steven Blum, Courtenay Taylor, David Ogden Stiers, Robin Atkin Downes, Jeff Bennett, Jennifer Hale, David Kaye, Fred Tatasciore and Julian Holloway . </P> <P> Each episode of Regular Show takes about nine months to complete . Quintel and his 35 - member team develop each episode at Cartoon Network Studios in Burbank, California . The script is illustrated in rough hand - drawn images, known as storyboards . The storyboards are then animated and mixed with the corresponding dialogue to create the animatic, which is then sent to be approved by the network . The show's assets (backgrounds, character designs, props) are then assembled to be sent to Saerom Animation in South Korea, where the actual animation production of the episode is performed . When finished, the episode is sent to Sabre Media Studios back in California . Music and sound effects are created and the final episode is mixed and completed . The process allows the production team to work concurrently on dozens of episodes at different stages of production . </P>

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