You can play for free until September 23rd. (all users)
The PC version can be played for free on Battle.net.
https://www.xbox.com/ko-KR/games/store/iv/9NQRCD3W41L3/0010
discount sale
Regular version (62,400 won 37,440 won)
https://www.xbox.com/ko-kr/games/store/p/9N8117TM8JL3/0010