This thesis deals with the phenomenon of DLC in the context of marketing communication. DLC or downloadable content expanding the basic game, is a relatively new concept in the video game industry and its role is increasingly important in marketing communication in video games. The main focus of this thesis is to map DLC and analyze its importance in marketing communication and public relations of video game titles of various genres. Theoretical part of the thesis is focused on explaining the basic principles of understanding a video game as a medium, the specifics of gaming industry and description of the DLC itself as a content and marketing tool in video games. The research part of the thesis is dedicated to three case studies which deal with video games of different genres. Case studies are focused both on the practice of video game publishing companies and on reception of DLC on the side of the fans. The games being focused on are The Witcher 3 (RPG or a role-playing game), Civilization V (strategy game) and Battlefield 4 (FPS or first-person shooter game). Case studies focus on the role of DLC in games, marketing communication about DLC and conversely its role in marketing communication, reception of DLC in gaming communities and specific functions of DLC dependent on the video game genre.