Demon Beast

Demon Beasts (魔獣 Majuu) are monsters that possess magic power.

Information
Demon Beasts are rumored to have been created by a witch to wipe out humanity. They eat mana and any Demon Beasts that have their horns broken follow whoever broke it.

In actuality, Demon Beasts were created by Daphne in an attempt to eliminate starvation from the world. Born "somehow" through her mind and feelings, they were made to eat mana so as to not need a habitat or food, and were made to grow larger and larger to increase the amount of food they would be able to provide when killed. However, because of these two traits, Demon Beasts became far stronger than Humans, causing them to start targeting Humans themselves.

As they were thought to be attracted to the miasma of witches, Magic Beasts were long thought to have a connection with the Witch Cult, however Anastasia has pointed out that they actually try to avoid it.

Three Great Demon Beasts
The Three Great Demon Beasts (三大魔獣) are a title given to three Demon Beasts that caused the most damage to humanity. They are recognized to be a type of disaster and are given special caution when they appear.

Oousagi
The Oousagi (大兎) are fist sized white rabbits with long ears. Their main food source are Humans, and once they finish eating any creatures in their vicinity, they will begin eating each other while they move around to look for another food source. While they are weak on their own, the number of Oousagi total to the number of water drops in mist, and they will keep on dividing and multiplying unless every last one is killed. Unlike other Demon Beasts, Daphne projected her own sense of starvation onto them, and when Subaru experienced the same sense during his encounter with her, he feverishly began eating his own right arm.

Kurohebi
The Kurohebi (黒蛇) is known to plague its victims with a hundred diseases just by touching them, and any ground that it slithers over is cursed, making anything except Demon Beasts unable to live on it. One person that came into contact with its tongue was scarred with reddish black burns, another had their skin from the neck up covered in reddish black spots that gushed black blood, and another had their body dried up to the point that touching them might break their body apart.

Unlike the Oousagi that can be directed to places and the Hakugei which is under the control of gluttony, the Kurohebi is uncontrollable, obeying no one as it moves from place to place. The Kurohebi is rumored to be a snake, though no information has been given about it, however a slithering sound has been heard.

Hakugei
The Hakugei (白鯨) is a large white whale Demon Beast that is able to release mist that can cover its surroundings. The mist is actually the mana of the Hakugei that has been modified. The mist, dubbed the Mist of Elimination (消失の霧), is released from the many mouths across its body, and is capable of erasing victims along with any memories the surroundings has of them. It can also break the spirits of those unprepared with its roar and when faced with heavy attacks it will spawn clones and escape into the sky. Although unconfirmed, Ley Batenkaitos claims that he could potentially breed and raise the Hakugei if he was given 400 years to do so. The Hakugei was killed by a combined force of members from the Emilia, Crusch, and Anastasia Camps, with Wilhelm dealing the final blow to avenge his wife.

Wagpig
Wagpig (岩豚/ワッグピッグ) have round red eyes and jet black skin that's thick and hard like rock. They have a large mouth seemingly capable of swallowing a Giant whole and flat teeth.

Guiltylowe
Guiltylowe (ギルティラウ) have the head of a lion, the body of a horse or goat, a snake like tail, and a large body capable of blocking a wide passageway. They are known to be a "boss" like beast, often living deep within forests with a high concentration of mana, with some preferring not to needlessly roar like other Demon Beasts. Contrary to their large stature, they lightly move around, silently killing their prey with one blow to their vitals, and are skilled at ambush and assassination like hunting. They are also known as the Jet Black King of the Forest (森の漆黒の王) and Shadow Lion (影獅子)

Black Winged Rat
Black Winged Rat (黒翼鼠) are rats that have black wings, making them similar to bats.

Ulgarm/Juggernaut
Ulgarm (ウルガルム), originally known as Juggernaut (ジャガーノート) in the web novel, have black fur, a salivating mouth with razor sharp teeth, red eyes, and looks like a wolf. They are around one meter in length, weigh 30 to 40 kg, and have a yellow horn on their. Juggernaut are able to cast a curse on others which enables them to steal mana from a distant target, stealing mana from their victims when they become hungry. One of these lived near the Roswaal Mansion and was briefly known as the shaman until it was killed by Subaru.

Abonsconda
Abonsconda (双頭蛇/アボンスコンダ) have two heads and a body as thick as a human arm.

Banassi
Banassi (袋鼠/バーナッシ) can change their body size based on their anger level. They leave traps at dead ends and strike the moment their prey becomes careless.

Spotted King Dog
Spotted King Dog (斑王犬) have four legs with sharp claws and thick fur. They have spotted fur and are similar to hyenas, however they are twice as large as humans.

Augria Sand Dunes
Due to its close proximity to the Witch's Shrine, the Augria Sand Dunes has a high concentration of witch miasma, making it an ideal place for Demon Beasts to live. Demon Beasts that live here are larger than normal, tend to become violent, and some only live in the area.

Ikkakujuu
Ikkakujuu (一角獣/いっかくじゅう) are rumored to be an endemic species that live in the Augria Sand Dunes. They have only been mentioned by the bartender in Mirula.

Oiranguma
Oiranguma (花魁熊/おいらんぐま) are a bear shaped Demon Beast originally from Kararagi that have flowers all over their body. They live in flower gardens that exist in certain areas of the Augria Sand Dunes. Oiranguma are two to three feet in length, have short legs in exchange for long arms, black fur, and hook like claws. The flowers on their bodies are actually parasites that suck moisture and nutrients from their hosts, and any places that don't have any flowers have withered, their faces mummy like.

Gabaou
Gabaou (餓馬王/がばおう) are an endemic species located underground in the Augria Sand Dunes and are one of the strongest species that live there. They are six to seven meters in length, have a horn instead of a head, no eyes, a mouth that stretches from their chest to their stomach, and a cry similar to a Human baby. In exchange for not having sight, their hearing is above average, using echolocation to see their surroundings. The fur on their back is constantly burning and keeps on burning even if it is pulled out, allowing them to launch fireballs at their prey or create weapons for close combat.

Unlike other Demon Beasts, Gabaou are able to regenerate a broken horn, making them unable to be tamed, and can also regenerate any lost body parts in addition to adding limbs or hardening their body, effectively enabling them to make themselves stronger after they meet their opponents. Despite their strength, they were easily defeated by Shaula.

Sunamimizu
Sunamimizu (砂蚯蚓/すなみみず) are an endemic species located in the Augria Sand Dunes, though there are native ones as well, however the endemic ones are considerably longer. They have no backbone, no eyes, no arms or legs, and has a body that is made to live under the surface. Their mouths are capable of swallowing four to five people whole at once and have teeth that help distribute saliva that melts their victims.