The Vangaak was an aquatic trawler used by the Yuuzhan Vong for traveling underwater. The living craft's skeletal frame was composed from tough yorik coral. Once the frame matured, it was seeded with a living organism called kera-boa, which reproduced rapidly, creating a semi-sentient protoplasmic colony which sprouted millions of long, microscopic tendrils that dangled below the craft. These tendrils were made to move together and could propel the craft in any direction. After the kera-boa system had taken root, the Vangaak was enveloped by hundreds of long, tough dull green scales supplied by the dora-mu, which was an aquatic creature imported from the Yuuzhan Vong galaxy.
However, those green scales did not die upon removal from the dora-mu, because it could mold itself onto the Vangaak's skeleton and receive nutrition from the living craft. These scales were also able to withstand blaster bolts, and were capable of healing. Also, knobby projections that can control the craft sprout from the carapace. Vangaak trawlers were used to gather fish and other aquatic life. It traveled largely submerged with only a broad flat dome that served as a sensory device visible.
The Vangaak fed by opening a large maw at the front of the craft which could suck in fish. The water was filtered through thick, sticky strands of kera-boa tendrils. Large organisms got caught in the web while smaller ones passed through the kera-boa tendrils into the Vangaak's digestive membrane, which fueled the craft. Larger variants of the Vangaak could be used for aquatic combat with the addition of specialized yaret-kor. They could also be used as sea-going troop transports and could board enemy vessels.
- The New Essential Guide to Vehicles and Vessels
- The Complete Star Wars Encyclopedia