John and Jacob silently waited in front of the teleportation array to greet all the other six Beast kings. The status power and influence of the Beast kings were so high that John personally waited to welcome them to his territory.
Even if John was the third strongest Beast king, it did not mean that he could ignore the other Beast kings. The other Beast Kings cannot be underestimated. Each of the beast kings had grown so powerful and influential that if two of them started fighting amongst each other even and if one of them were to win, the resources that would be used to defeat the other beast King would be simply too much. Even if the other Beast King were to win, the casualties would be too much.
In short, the price of taking down one Beast King and his army would be simply too much. The consequences weren't something that any of the Beast Kings could bear even if one side won.