Diablos are hard-shelled Wyverns, commonly found in the Desert region. Their name "Diablos" means both "Two Horned" and "Devil". They are easily recognized by their trademark dual horns protruding from their head, which also sets them apart from their close relative, Monoblos. They have tough skin and even stronger heads, which they use as their primary weapon.
Diablos have the ability to dig and travel underground, but can easily be unearthed with a Sonic Bomb. However, Sonic Bombs do not work when Diablos is enraged, due to its increased tolerance to high-frequency sounds. They are one of the most feared monsters living in the desert, even though they are actually large herbivores. It has been theorised that their horns become weaker and more brittle with age, as some individuals can be found in the Desert with only one horn - although it is possible these individuals lost a horn due to a battle with another Diablos. The Diablos can produce a High-Grade roar which normal Earplugs do not work against.
Wyverns feared as desert tyrants. Extremely territorial, Diablos attack invaders with blind aggression. Highly sensitive to sound, perhaps because they frequently travel beneath the sand. Known to feed on cacti.
The design of Diablos is directly inspired by a Kaiju (Giant Monster) , although no particular one was mentioned.
In Monster Hunter Freedom Unite there are two High Rank quests featuring a unique Diablos: one in the Guild and the other from Nekoht, the Felyne Elder. In these quests, players fight the one-horned "Demon King Diablos", which has higher health than a Diablos of the same rank, and higher attack and defense than any Diablos.
Diablos, along with Rathalos and Rathian are the only Large Monsters from the original series that appeared in Monster Hunter Tri.
Most Diablos weapons have negative Affinity, ranging from -5% to -50%. An exception to this is Chaotic Order and the Ebony King Bow (The latter actually has 20% positive affinity). To balance this downgrade, they have great raw power and good white and purple (with Sharpness+1) sharpness.
HC Diablos has a new more powerful look, it has very very large horns, vein covered stronger wings,and more muscle mass. It also has new moves and behavior. When it digs it will pick a target and dig back out at surprising speed leaving a trail of large rocks raining everywhere it digs and a new tail attack.
On Monster Hunter Frontier Online Diablos can be a pet. Along with eating cactus, it is known to love eating Yale Nuts found in the Gorge and rarely the Tower, along with the rare Dosubisukasu flower from the Tower
Even though it is a herbivore, a Diablos is seen attacking a Cephadrome used as bait by Curlon Belusas in the Monster Hunter Orage Volume 2. She's seen with the Cephadrome in her mouth, even though it's normal for her to attack with her horns.
In MHP3rd and MH3U, Diablos has a new attack, taking the form of a quick lunge forward.
Diablos gains a new move: after a series of tremors, it will catapult itself out of the ground towards an unfortunate hunter.
Normal Diablos never uses this move in Monster Hunter Portable 3rd at Low Rank, and only uses it rarely at Upper Rank (unlike Black Diablos). However, it gains a different move instead: it can quickly charge forward, damaging hunters in its path.
There is no longer a Waist and Legging armor for Diablos in Tri (just like in MH1).
However, this is no longer the case in Monster Hunter Portable 3rd and Monster Hunter 3 Ultimate, in which an entire set can be crafted with Diablos components.
The run and dive can now be used to avoid Diablos' roar unlike in previous games.
Diablos can now be trapped in a Pitfall Trap.
Diablos is able to perform an uppercut after a ram, and is also able to perform 2 uppercuts chained together, like many Brute Wyverns do.
Diablos is now faster getting out of the ground on which the hunter stands upon. Unlike in previous games, Diablos doesn't give time to sharpen weapons, reload bowguns, drink potions, etc. The hunter has approximately 0.10 seconds to get away from the Diablos when it's underground, then 0.05 when in Rage.