Today was the first day of the sophomore year, the Elite Class were introduced to the norms by their head teacher Xue Musheng who had the best freshman class last year.
Mo Fan was only allowed ten days with the Star Dust magic tool instead of a month while Mu Bai had the same amount and he had seven days, one circulation of the magic tool would be two months. In fact over the course of two months both Mu Bai and he would have more days than Mo Fan as they were the biggest beneficiaries of his outburst.
The next ten days was important to him as his first plan needed to be realised. The only reason Mu Zhuoyun reduced Mo Fan's time with the magic tool was so that his failure against Yu Ang would be more dramatic and not because he appreciated Mu Bai, in his mind Mu Bai was worse than Mo Fan who was worse than Yu Ang.
In this case if Mo Fan lost to Mu Bai instead of Yu Ang wouldn't it be more degrading, it was this line of thought that he needed to introduce into Mu Bai and Mu Zhuoyun, in fact through Zhao Kunsan he already knew that Mu Bai didn't have any time with Star Dust magic tool in the Mu family now since he was being given extra time on the school's device, he needed to change that.
After he hints for a few days Mu Bai introduced the idea to Mu He instead of Mu Zhuoyun since he appreciated him more ( Mu Bai doesn't yet know that Mu He is his father). A father still has some appreciation of his son and he hoped to induce Mu Bai to the Black Vatican as well and decided to test him as well, but fortunately for Mu Bai it was a test he was doomed to fail.
After Mu He's words Mu Zhuoyun ultimately gave Mu Bai another chance and gave him the Star Dust magic tool Mu Ningxue stopped using after she was noticed by the main family for one condition, the day before the duel Mu Bai had to challenge and hurt Mo Fan so that he wouldn't even make an appearance the next day, Mu Zhuoyun also asked to make sure Mo Fan was eighteen at the time of the challenge and as close as possible to the official duel.