The young palace master gave them a few pills, and after that, their body started to change, and it was then that they became half-orcs. Creatures like them who had practiced to their level would usually hide their monstrous appearance when they were in the outside world, disguising as human beings.
Apparently, the young palace master had refined the medicine she needed three times, yet all three attempts failed almost right at the end. Each attempt required her to sacrifice eighteen children; so, there were already fifty-four children who were killed.
This was also the main reason why the young palace master was intrigued to learn that Mr. Fuyi was able to make the pills successfully on the first attempt; she treated Mr. Fuyi with utmost respect and politeness.