Portal: Revolution isn't official, but it is an incredibly impressive-looking mod with an original story

Those that are craving a whole new Portal adventure will probably be interested in Portal: Revolution, a big new mod filled with new puzzles and original voice acting. We're probably not going to get another Portal game from Valve any time soon, but thanks to the series' modding community, there's basically an entire new entry you can play right now. And as it's a mod, it's completely free too! Set between the events of Portal and Portal 2, Portal: Revolution sees you as a new, unnamed test subj...