Dark Horse Comics has revealed that it will be releasing a book that compiles together all of Valve's video game related promotional comic strips. Valve Presents: The Sacrifice and Other Steam-Powered Stories will contain over 300 pages of comic strips previously released individually online to promote various Valve releases, according to Comic Book Resources. The main bulk of the book will feature The Sacrifice, the strip released online alongside Left 4 Dead 2, with comics revolving around the worlds of Team Fortress 2 and Portal also featured. The book's description, as provided by Dark Horse, describes it as "a must-read for fans looking to further explore the games they love or comics readers interested in dipping their toes into new mythos." The comic book will go on sale on November 16, and cost $29.99 RRP. Last month, Valve made a number of big changes to its game library, first releasing team-based shooter Team Fortress 2 as a free-to-play title, and later releasing its Source SDK freely to the public.