- Order: Saurischia
- Suborder: Wyvern Feet
- Infraorder: Heavy Shell Wyvern
- Superfamily: Horn Wyvern
- Family: Blos
Black Diablos is a female Flying Wyvern in heat, though considered a Subspecies by the Hunter's Guild. Normally, a normal Diablos until Breeding Season, Black Diablos are a highly aggressive female Diablos. Its closest relatives are Monoblos, White Monoblos, Varusaburosu, and Gravios.
Contrary to popular belief, the Diablos and its one horned relative, the Monoblos, are herbivores that readily feed on any kind of vegetation in their territory. Males often live so long and engage in so many battles that they will sometimes lose one of their horns. Diablos in the New World are known to feed on giant cacti which can reach sizes of up to 12 foot tall. But with the size of the plants also comes rarity, so Diablos are always on the look out for these rare and succulent food, which leads to frequent territorial disputes. In desert regions, these wyverns coexsist with fearsome predators such as Tigrex, Brute Tigrex, Nibelsnarf, Rathian, Kuarusepusu, Sand Barioth, Odibatorasu, Deviljho, and rarely Elder Dragons.
The Wildspire Waste's dominant native monster, the Black Diablos patrols her territory with an iron fist and is ready to charge at any monster who is foolish enough to step in her domain, even other Diablos. The Black Diablos is much more aggressive than their standard counterpart, especially at the sight of hunters. She is also far stronger than regular Diablos and is much more keen to fight back against invaders and Elder Dragons, even if it's a fight that she may lose.
Black Diablos have many of the same adaptions as Diablos, however, there is some differences between them. Due to the Breeding Season, Black Diablos have changed color in order to warn other species to avoid them. This is from Black Diablos being far more aggressive than normal Diablos during this season. Though it can briefly be seen, a Black Diablos's hide will occasionally change to brown when angered. For unknown reasons, the horns and even shell also become stronger while in the Breeding Season for female Diablos.
Some rare female individuals have a unusual purple flesh, as well as more spikes on their frill, body and tail. They also have one horn unusually longer than the other, are able to dig with such force they cause strong quakes as they dig, and roar so loud they make a wind shield around their body. These females also use unique charging and attack techniques compared to common Black Diablos.
Interestingly, female Diablos are larger than males.
Black Diablos are very aggressive hormonal monsters, making them a species that is best avoided during the Breeding Season. Though mostly solitary, female Diablos are known to pair up with male Diablos during this season for a short period of time.