A Hydra craft was a repulsorcraft used for transportation over water. This was the primary mode of transportation on Drexel.
A hydra-skimmer version.
The hydra craft was a small aquatic repulsorlift gunship. The craft was typically equipped with laser cannons and magnetic grapples. An armored type of Hydra craft was called a hydra-skimmer.
They were used by the ship-dwellers to salvage wrecked ships and fight Dragon Lords. During the Battle of Drexel, hydra-skimmers were used as gun platforms, both against the dragons, as well as against the Millennium Falcon.