"Cerys Character Card":
As the ultimate abode of the Evil Spirit and a witch who controls blood and night, you should possess powerful enchanting abilities. When transformed into Cerys, you can employ the "Fantasy Dream" ability to drag the target's consciousness into an abyssal dream, where you decide what they encounter.
Special Skill "Rose Sonata":
Anyone who hears this song will succumb to it. When using the Cerys Character Card, this skill can be activated to hypnotize targets who hear the melody.
This is the solution proposed by Xu Shuo.
Subverting the Messenger may not be a necessary step, but if he can be used to buy time or even confuse the view from the Royal Capital.
Then it would undoubtedly be beneficial for them.
All in all.
Just as sending this Messenger is a risk-free move for the Royal Capital.
So is subverting him for them.
Oh, but actually it's not.
After all, the opposing side receives false information.