After leaving Xujia Village, Iron-Dragon Airboat parked in Xingyu City for supply.
It was Zhang Tie's first time to replenish materials for his airboat after leaving Fire Dragon Bounty Territory. Although airboats of Taixia Country didn't need to replenish energy and fuel, people in the airboats had to eat and drink.
The central dynamic and suspension system of airboat was made of a metal called floating metal. It was said that this rare metal came from a mysterious place in Earth-elements Realm. As of now, only the imperial household of Taixia Country could get hang of the technique of making airboat using floating metal. It was said that this technology originated from a prehistoric civilization. Benefited from this technology and this special metal, airboats would never run out of energy.