Keys is a short first person art installation that provides a visceral and thought provoking experience combined with rich environments and striking imagery. It is greatly influenced by our admiration for games like Good Morning, Commander, The Barista series, Kairo, and Radiator.
All you need to get going is a game that grants access to the Source SDK Base 2013 Singleplayer, and to have it installed. There's no reason not to give it a go.