We were teleported to an unknown location in the depths of the Aperture Science Laboratories. Portal Revolution Chapter 5 set us up to be completely alone and helpless... are we REALLY alone though???
Fun fact, the Pneumatic Diversity Vent is a cut testing element from portal 2. Its said because they seem really fun and cool. It wasn't added though, because the playtester say no use for it other than sucking up turrets. It has a full video on Valve's youtube channel, though.
