Looking at Ferdinand's demeanor, Muria knew that the upheaval in Yas Country definitely had something to do with him. He guessed that Ferdinand was one of the masterminds behind it, and he believed that more than one person was involved.
After all, Gai Nation was just a vassal state of Yas Country, and its capacity was clear. Even though Ferdinand was talented and ambitious, he lacked a sufficient foundation to exert his influence.
He had spent decades planning, and all he had managed to do was cause turmoil in Yas Country. However, turmoil was an opportunity for the surrounding smaller nations to weaken the hegemony of Ymir Plain and strengthen themselves.
The seven equally powerful heirs to the throne in Yas Country were probably the result of Ferdinand collaborating with other ambitious figures. After the old King's death, these seven "excellent" heirs would divide the entire country into seven parts.