https://blog.faceutil.com/2017/03/12/rpg-%ed%99%98%ec%84%b8-%ec%8b%9c%eb%a6%ac%ec%a6%88-%ed%95%a9%eb%b3%b8-%ed%99%98%ec%84%b8%ec%b7%a8%ed%98%b8%ec%a0%84-%eb%93%b1-%ea%b2%8c%ec%9e%84-%eb%aa%a8%ec%9d%8c%ec%a7%91-%ec%bb%b4%ed%8c%8c/