아에 install이 끝나야지 되는거고 아니면 사라지고 원래돈으로 바뀐다고하네요 ;;;
You need to be sure to install the game to secure your license. If you don't, it returns to its regular price tomorrow and will disappear from your library. Unfortunately, the volume of users trying to download the game has crashed the service.
https://www.gameinformer.com/b/news/archive/2013/12/25/left-4-dead-2-free-until-tomorrow-morning.aspx
