149 A prototype.

Gu Yijin has once told them about a sect that was so deeply engrossed in dark arts that they tried to make an army of vengeful spirits to do their bidding but they couldn't do it, in the end, they tried to create a prototype that was just as strong as an army of vengeful spirits and after many trials and errors, they finally succeeded. She still remembered how serious Gu Yijin looked when she told them about just how difficult it was for her family to rein in those prototypes and destroy the sect, apparently, at least fifty disciples and twenty masters died while they tried to stop the sect.