Leprechauns

Leprechauns (レプラカーン, Repurakaan) or Golden Fairies (黄金妖精, Ougon Yousei) are a race of fairy-type Disfeatured creatures who are thought to be created from the souls of the children who couldn't comprehend their own death. They are currently used by the Guardian Wings Military as their secret weapon against the Seventeen Beasts.

Background
Leprechauns are a race of beings that came into existence over 500 years ago. They were originally said to be created from the spirits of children who were too young to comprehend their deaths and thus are said to be a race of spirits. However, in truth, Leprechauns are actually the creations of the Visitor, Elq Hrqstn who died as a child and had her soul shattered. Being unable to process her death, Elq's desire to be like Lillia Asplay, a Regal Brave who fought for what she loved, resonated with her fragments and created the very first Leprechauns.

All Leprechauns have a life span of roughly 20 years or more and have short lives. But, they do carry the potential to be reincarnated upon death. This reincarnation may not always be immediate and they don't end up with the same bodies as last time normally. Also, they seem to be loop reincarnating as can be seem by Ithea's situation.

Biological Features
Leprechauns are a female only race and it is currently unknown if they can actually have children. But biologically, all Leprechauns look similar to Emnetwiht humans. Originally, they appeared in smaller incarnations and were no bigger than a person's hand. But, as they constantly reincarnated, they gradually became more human-like.

Like Emnetwihts, they also have the ability to spurt rainbow colored butterfly wings from their back to enable them to fly. All Leprechauns are also unique in that they Venenum manipulation abilities, where they can use Venenum to spurt wings or power up their attacks. However, the more they use Venenum, the quicker Mental Disintegration will set in or they'll burn out their lives as a result.

Dug Weapon / Tuning Process
All Leprechauns are also unique in that they have the potential to wield a Dug Weapon thanks to their Venenum manipulation abilities, however, most do not awaken to this ability. For the ones that do, they awaken their potential by having a strange dream called a  'Harbinger Dream' where a Leprechaun dreams that they are in a unknown place, talking to an unknown person. They can also differentiate this dream from normal ones and can normally tell when they are ready.

When they do have this dream, all Leprechauns are required to go to the hospital in Corna di Luce on Sky Island 11 in order to be tuned to be compatible with their Dug Weapons and to enable them to grow up safely. Upon arrival at the hospital, Dr. Margomedari Brompton and his nurses gives them a basic checkup and perform tests to determine the risk of Mental Disintegration within them. The Leprechaun is then treated for any cavities or illnesses that they may have and stays there overnight. In the morning, the Leprechaun gets an injection in the morning and are allowed to leave soon after.

Venenum Instability
Like Emnetwihts, they also have the ability to use Venenum which they normally use to spurt rainbow colored butterfly wings from their back to enable them to fly. However, due to them being fragments, Leprechauns are highly unstable beings and if they are not careful, their Venenum could spiral out of control and cause a explosion.

Physical Breakdown / Sleeping Sickness
Sleeping Sickness is a form of physical breakdown which occurs during the time when Leprechauns have the Harbinger Dream, a strange dream which shows Leprechauns images of places that they have never been to or of people that they have never met before. After a Leprechaun has the Harbinger Dream, in order for young Leprechauns to become adult Leprechauns, a tuning process where Leprechauns have their bodies tuned with a Carillon / Dug Weapon is required to necessitate this change.

However, if a Leprechaun who has the Harbinger Dream has their tuning postponed or halted for some reason by the Guardian Wings Military, then that Leprechaun is at high risk of dying from both a physical and mental breakdown. During this breakdown, a Leprechaun will start this transition by going to sleep more often. This is followed by sleeping for longer periods until they sleep for hours or even days at a time, lost in their dreams. Eventually, the Leprechaun will then fall into a coma and die, if left untreated.

The only way to fully cure this breakdown is for the Leprechaun to undergo tuning. However, there is a way to delay the effects through medication, but, it is only a stop-gap measure at best and cannot permanently cure the disease.

Mental Disintegration
Due to their unstable nature and connection to Elq, all Leprechauns possess the risk of Mental Disintegration. Mental Disintegration is a phenomenon where the Leprechaun will start remembering scenes from their past lives and gradually have their minds and bodies subsumed by either Elq Hrqstn or their past life, leading to the Leprechaun's death. The process can also be hastened if the Leprechaun expends even a little Venenum and during this process, some of the symptoms that a Leprechaun might suffer are: Not all cases of Mental Disintegration are the same though, as full on 'Past Life Possession' is also possible for the Leprechaun.
 * Hallucinations;
 * Visions of Past Lives;
 * Memory Loss;
 * Loss of Emotions / Personality; and
 * Comas.

Past Life Possession
In some cases, Leprechauns like Ithea have actually had their bodies taken over by their past lives. These past lives are normally not aware of they originally were. They just know that they have taken over somebody's body and some eventually learn to mimic the person who once held that body.

In Lakhesh's case, however, she was fully possessed by her past life, Elba, who had full access to her original memories, due to the immense grudge she held against the Guardian Wings Military.

Special Abilities

 * Dug Weapons Usage - All Leprechauns are also unique in that they have the potential to wield a Dug Weapon thanks to their Venenum manipulation abilities. The Dug Weapon that a Leprechaun normally gets depends on the owner's personality and whether or not the swords likes them.
 * Fairy Gate - The Fairy Gate is an immensely powerful attack, that allows a Leprechaun to release their full powers in one blast. However, it takes the Leprechaun's life in the process.
 * Timere Sensing - Leprechauns have developed the ability to sense Timere, as a result of all their years fighting beasts. They can normally tell when they are about to attack and which Sky Island, they are gonna appear on.

Known Leprechauns

 * Elba Affa Muresmaurea (Deceased)
 * Nasania Will Percham (Deceased)
 * Chtholly's Admired Senior Fairy (Deceased)
 * Orco (Deceased)
 * Tuca (Deceased)
 * Weldié (Deceased)
 * Rona (Deceased)
 * Chtholly Nota Seniorious (Deceased)
 * Ithea Myse Valgulious
 * Nephren Ruq Insania (Deceased)
 * Nopht Caro Oracion (Formerly Nopht Keh Desperatio)
 * Rhantolk Ytri Historia
 * Tiat Siba Ignareo
 * Lakhesh Nyx Seniorious (Deceased)
 * Collon Rin Purgatorio
 * Pannibal Nox Katena
 * Almita
 * Ryehl
 * Apple (Deceased)
 * Eudea
 * Ilstoot
 * Dillfay
 * Masha
 * Sarya
 * Eculecra

Trivia

 * Once known as fairies. Some people complain about its use in the series, however a leprechaun is actually described as a type of mischievous fairy, and its female form isn't popular in western fantasy, which makes the complaints unfounded.