Vaal Hazak is a grotesque elder dragon that inhabits the deepest part of the Rotten Vale of the Milsk'huikol Universe. It uses the fatal vapor of the vale in what appears to be some kind of symbiotic relationship.
Vaal Hazak is a long, slender Elder Dragon with several unique physical features. Its body is covered in silver scales, which are obscured by the fleshy red veil that covers most of its body. It possesses a striking double lower jaw, each with a row of extremely long, sharp fangs similar to those of a deep sea fish. It has two bright yellow spots at the sides of its head and two small red eyes. Its toes and wingtips are adorned with sickle-shaped claws. It is similar in size to other Elder Dragons such as Teostra and Kushala Daora.
Vaal Hazak is capable of covering its body in a mysterious, life-sapping miasma, known as the Effluvium. As the substance builds up in the body of its victim, it can cause severe weakening of physical strength and resilience. The monster is able to release this miasma more violently by spewing a concentrated stream from its mouth or spreading it around a large area as a noxious cloud. Vaal Hazak also possesses the ability to gather the Effluvium from affected creatures back into its body, healing itself and killing the victim in the process. Despite its size, its lithe nature allows it to move around at high speeds and even leap considerable distances at prey.
This dragon lives a solitary lifestyle, and does not allow other monsters to encroach upon its territory. While it may not always react to the presence of a hunter, it will immediately become aggressive with any large monster it encounters. They are known to bury themselves in the piles of bones which litter the environment.