Hotburple

The Hotburple is a Boulder Class dragon that appears in How to Train Your Dragon 2.

Development
The Hotburple is inspired by a walrus, tadpole, old bulldog and trash can.

Egg
These dragons' eggs are oval in shaped. They have large, smooth bumps all over it, just like those on an adult's body.

Hatchling to Adult
Hotburples' greatly resemble Gronckles', although they have a larger body and wings, as well as their eyes being positioned closer to the snout than to the ears. Hotburples' also appear to have a larger tail bludgeon and a slightly smaller jaw, but with sharper and smaller teeth compared to Gronckles'. Like Gronckles, Hotburples have tough body scales and hard bumps all over them.

Titan Wing
Titan winged Hotburples have different shades of blue and white as well as large dark blue spots on their body. Spines run along their body lengthwise and their initially significantly clubbed tail has been reduced to a smaller tail. They have grown a lot larger and stockier in built.

Jaw Strength
Just like Gronckles, their powerful jaws are able to crush boulders and iron. They are able to feed off it and use it to create a powerful lava blast.

According to Ryker, Hotburples are the only species that can bite through Dragon proof metal.

Speed and Agility
Their flying speed however, is the same with Gronckles, even though Hotburples possess larger wings.

Strength and Combat
Their large, powerful clubbed tail can knock multiple people unconscious as seen in the second movie. They are able to carry heavy Vikings with a heavy settle chair, which means they are stronger than Gronckles. Just like Gronckles, they can possibly use their nose horn and their head to charge and bull doze their enemies.

Durability and Stamina
Having a high defensive armored body, their endurable body is greater than Gronckles. They have great stamina as Grump had shown to be able to travel long distances with his rider on back.

Sleep Flight
If they get exhausted from flying, they have a special ability which allows Hotburples to continue to fly when they fall asleep. Gronckles however, tend to fall out of the sky, crashing into the ocean or the side of a mountain.

Firepower and Recharge Abilities
Just like Gronckles, they possibly can recharge their shot limits by feeding off rocks or scrap. They rival that of Gronckles' in being heavily armored and can fire devastating lava blasts after digesting the metal ores that they eat. Their high strike power rivals that of the Night Fury.

Behavior and Personality
They are much more lazy compared to Gronckles, as they sleep more and snore even louder.

They might have the personality of a really lazy cat, which is opposed to Gronckles, which have a bit of a bull dog like personality. They have a high appetite for minerals and iron, but mostly scraps. Hotburples' have a usually laid back disposition, but are not to be messed with as shown in their debut episode.

Despite this, they can be incredibly aggressive and hostile if faced with crisis. This can be displayed when Grump, the supposedly dociile and tame dragon attacked the Dragon Hunters to save Gobber.

Weaknesses
Hotburples are one of the laziest dragons there are, possibly even lazier than Gronckles because Meatlug was awake for the full second movie whereas Grump was asleep for most of it. They also are very slow and clumsy, as well as always falling asleep. However, when sufficiently angered, a Hotburple becomes far more active and dangerous, making up for said weaknesses.

How to Train Your Dragon 2
Grump, a Hotburple, was first introduced in this film. He worked alongside Gobber in his Blacksmith Shop, keeping the forge lit with his fire. He and Gobber also accompanied Stoick and Skullcrusher on their search for Hiccup and Toothless, who were taken to the Dragon Mountain by Valka.

Season 3
In Last Auction Heroes, Grump, served as Viggo's personal garbage disposal, eating all the scrap iron at the Dragon Auctions on Dragon Hunter Island until he met Gobber. He was taunted and mistreated by every man on the island, especially Ryker, who believed that he'd be more useful as food. But Gobber was quite taken with the large and ungainly dragon, showing Grump some respect for the first time in his life. His true strength and potential are revealed when he takes out two underestimating guards and frees Gobber and the Dragon Riders from a dragon-proof cage by simply biting off the door. He and Gobber then join the other riders as they fly home to Berk.

Dragons: Rise of Berk
The Hotburple, along with its Titan form, appeared in Rise of Berk. Grump and an exclusive Hotburple, Basket Case, also became available in this game too.

School of Dragons
The Hotburple also became available in School of Dragons.

Trivia

 * While Gronckles like to eat any type of rocks, Hotburples prefer to eat ores of metal, such as iron.
 * It is unclear whether any other Hotburples share the half-closing eyelids of Grump.
 * It is unknown if Hotburples can blast off the bumps on their body like Gronckles.
 * It is said that the Hotburples are like a walrus, a bulldog, a tadpole, and a trash bin mixed together.