Knight Robinson interrogated the other dying frog nobles and learned from them that this was a private operation of Guiren Village. They didn't really want to kill the heir candidates.
They just wanted to find some blood food to eat.
As frog nobles, besides not having human bodies, they have a huge defect—they must eat human flesh. Although they won't die if they don't eat, eating humans is something like an addictive behavior to them.
An hour later, all the purple frog nobles were dead.
Meanwhile, Ivita and his companions had no plans to leave the underground dark river.
The reasons were twofold.
First, it was not easy to find such a good base in the desert area.
Second, the King of the Ancient Tomb, the Elephant Divine Weapon, and the Griffon Knights were so immersed in their battle that they had no time to concern themselves with them. Moreover, the previous attack was Guiren Village's own doing.