Han Xiao could assign all sorts of missions, and those that were in the challenging category were more difficult than usual. They were often large-scale mission, where every movement of the individual players could impact the final result. Therefore, they had to work together to complete the mission.
He had witnessed some missions that could affect the version, where millions of players fought for the same goal. Every player's actions earned contribution points, and the mission needed tens of millions of points to complete. Once finished, it would be the turning point of the entire storyline.