Pick up the crowbar of research scientist Gordon Freeman, who finds himself on an alien-infested Earth being picked to the bone, its resources depleted, its populace dwindling. Freeman is thrust into the unenviable role of rescuing the world from the wrong he unleashed back at Black Mesa. And a lot of people, people he cares about, are counting on him.
Underground is a map lengthing in around 5-10 minutes. The map takes place in a time right near the uprising. You play as Mark a person who had his train stopped in the woods by Overwatch and his wife was taken to City 17 while he was taken to City 14. Can he make it? It's your choice to find out.