Tried doing a search and didnt see anything on this, but if its a repost lemme know
Doing Shado Pan Challenge mode earlier and after Sha of Violence fight when you get to the part where you have to purify the defenders you can have the tank drag the first to mobs off to the side and cc them there. Then AT THE SAME TIME all 4 people click on the orb and you get credit for having all 4 defender's purified. This will allow you to skip a whole other group right before the boss giving you at least 3-4 minutes left on the timer to kill the boss.