All crossovers and events on the steam version are not in the gog store, dying light bad blood is not in the gog game and you cant buy bundle like "6th anniversary" or "dying light x left for dead 2" wich is sad. I enjoyed playing it and i continue playing it but its just an advertisment: this version have litteraly 4 poeple online in the servers and litteraly no event so after 120 hours of game i just recommand you to buy it on steam