- Order: Saurischia
- Suborder: Bird Feet
- Infraorder: Bird Wyvern
- Family: Hypnoc
Hypnocatrice are scavengers content to feed on the remains of carcasses with their specialized hooked beaks tearing off pieces of flesh small enough to swallow whole. When carrion isn't available these Bird Wyverns feed on insects, small animals,Sleepy fish and Sleep Herbs. Hypnocatrice have to be wary of predators in their habitats such as Nargacuga, Espinas, Rathian, Kuarusepusu, Tigrex, Abiorugu, Yian Garuga and Zinogre (as the fanged wyverns favor eating bird wyverns). However if cornered these creatures will unleash vicious kicks and dances slashing and stomping their target with their sharp talons and utilize their unique yet very effective "sleeping fumes".
Unlike other bird wyverns, the Hypnocatrice seems to grow feathers which are used to attract mates. The Hypnocatrice produces sleep-inducing powder from its Sleep Sac and usually mixes it with some saliva though they can blow it in fumes of gas. This concoction is used to put aggressors or prey to sleep so that that it can leave without a scratch. Its powerful legs contain very strong muscles which are used in killing prey and performing mating dances. Its tail seems to be the only remnant of being a true wyvern.
As Hypnocatrice is the closest-looking monster that fits the "Bird-Wyvern" description, it has a strong beak but lacks fangs or even molars for grinding its food, unlike Gypceros or Qurupeco. Thus, it has to swallow pebbles or smooth soil into its stomach to help it crush and break down its food. These pebbles and soil might be introduced to the Hypnocatrice at its moment of birth, and matures along with it to form a prized stone known as 'Hypno Bezoar' that hunters can obtain after killing the creature. The Hypnocatrice's sleeping gas, mixed with its weak stomach fluids, could have formed a whitish solution that solidifies on the bezoar, giving the stone its ceramic appearance.
Some rare unusual individuals have been known to appear to have reddish pink feathers, Red tinted beaks, reddish claws and a longer larger head crest. They dance aggressively on anyone who approaches, as these unusual Hypnocatrice are known for there surprising strength. Also oddly these unusual Hypnos make orange "Hypno Bezoar" how or why it does so is unknown.
Hypnocatrice, true to its passive nature, doesn't tend to kill its foes. Rather, it prefers to put them to sleep and run from the fight. However, when enraged, it will put its enemies to sleep, then do everything in its power to kill its foe. Although, if it's hunting for its offspring, it might put a small monster to sleep and carry them back to its nest.
As stressed before, Hypnocatrice perform mating rituals to find a mate. Once a Hypnocatrice is fully mature, and breeding season begins, its feathers will change color, from a rusty orange to a bright red and bluish mix. These extravagant colors are perfect for attracting a mate, much like most real birds. These Hypnpcatrice are called Breeding Season Hypnocatrice.