"This is awesome!! Are you ready? Let's go!!"

Riley grabbed your hand and began running. You don't know how you got here, Or who the boy in front of you was, But the place was dark. There was a slight fog, And a school. There were things with blankets on them for easy vaulting over and there sounded like there was some kind of thing in here with the two of you. You passed by tons of other people, Working on generators.. What was this place?