More and more these kids tested her limits on how she perceived them and she was still trying to decide whether or not she wanted to completely crush them or see how long they'd fare until they broke due to their own weakness.
They were still young youkai who still didn't understand the world around them and how relentless enemies may be if they so chose to ignore the fact that these children tried to stand up to them and treated them as adults.
Mifuyu decided to rip off the bandaid and show exactly what she meant.
Her body siphoned the ice in the walls, the ceiling and the ground beneath her and ultimately the audience chamber began to crack and the wall behind the back of the castle where the back of the throne was facing shattered entirely.
The blizzard from outside the castle now affected them and it was being absorbed by the Lord of Ice but for what they wouldn't know until she was done with what she was doing.