So you just need to kill 25 NPC, 26 to be safe and you're done gather point's once you hit 300! You need 300 points in total in order before doing the 5th boss (else once the 5th boss is dead he won't let you go on to the next bosses). Talk to Yang Lei(testing Leader) (or the bosses will not fight you until you do!) to start (this is the map of bosses and the order their in)