Prospect Of Unity.

They could have also teleported but the Supreme Alliance wanted them to see the immensity of the world and broaden their horizons. 

The Supreme Alliance wanted them to see just how large the ancient battlefield was to have a more complete understanding of how large the whole realm was and how large the void universe could be. 

The airship is not for only the two of them. There are other Supreme Beasts who just finished their rite of passage with him. They are accompanied by their mentors who are there to protect them during the journey. But each Supreme beast has the privacy of their own cabin. 

The airship also carries other types of cargo both living and nonliving. Some of these cargoes are slaves. 

His divine sense reached over to the requested port and said, "Bring me my recent purchase."

A voice came out from the inscription on his chair, "Do you mean the battle sage monkey in the livestock warehouse labeled d2fH70?"

"Yes." He confirmed.