Guest Stars Walton Goggins voices Cecil Stedman Zazie Beetz voices Amber Bennett Gillian Jacobs voices Samantha Eve Wilkins / Atom Eve Andrew Rannells voices William Clockwell Grey DeLisle Griffin voices Amanda / Monster Girl Zachary Quinto voices Robot Khary Payton voices Black Samson Kevin Michael Richardson voices Mauler Twins Mark Hamill voices Art Rosenbaum Fred Tatasciore voices Adam Jonathan Groff voices Rick Ezra Miller voices DA Sinclair Max Burkholder voices Matt Fred Tatasciore voices Professor Justin Roiland voices Doug Cheston Khary Payton voices Kyle