User blog comment:B214/Question and Answers 6/@comment-118.172.205.177-20160711144501/@comment-1359322-20160712052739

Actually, Cao Cao made Vali enter JD in a spar match when they were both in the Khaos Brigade. Cao Cao was using his BB, Vali eventually entered JD in that spar. But you should assume that neither side were serious in that spar match since


 * 1) Cao Cao didn't use all his abilities
 * 2) Vali was probably doing what he did in V4. He got interested and decided to use JD to have Cao Cao pull out his best.