The Forgotten

The forgotten (忘れられた Wasure rareta) as they are so vaguely named are a race of creatures ranging from humanoid to monstrous in appearance and can vary in intelligence.

Overview
The Forgotten are a race of monsters that originate from humanity. Typically it's theorized that they come from unruly souls but it's also thought that they come from humans who have cast away their humanity, though the real reason has not been revealed yet. Among the forgotten there exists 6 special ones that have been around for ages. They could be considered the bosses of Forgotten entities and there has even been a proposal that these 6 were never human to begin with but were the reason for their existence. These 6 are typically referred to as the Six Crowned (六冠 Roku-kan), they've been around for centuries and as for their goals that is unknown. While intelligent variants have been found it's unknown whether or not the Six Crowned are mindless or intelligent, but it can be said that considering they've been around for so long they possess a certain degree of survival instinct that's kept the executioners at bay.

Origin
The first account of the Forgotten was as early as the 5th century though it could be said that they've existed much longer.

Creation
As to how forgotten are created that is widely unknown. As said above nobody has really deduced the reason behind these creatures existence. What is known is that they may be connected to humanity as to how they're connected, that too is unknown. They aren't born naturally nor are they capable of reproducing or copulating for that matter. They can't be reproduced by each other through biting either so that too is out of the question.

Abilities and Powers

 * Inhuman Physiology:
 * Inhuman Physical Capabilities:
 * Immortality:
 * Supernatural Abilities:

Weaknesses

 * Artillery: while swords and knives have some effect it's been shown that artillery particularly grenades and guns can functionally put them out of commission or at least deal serious damage.
 * Core: Forgotten seemingly have a core within them as to where the core is, is an irrelevant question since all Forgotten possess cores in different areas and the stronger ones possess multiple cores ranging from 2 all the way up to 6.
 * Poison: although not the most effective it does seem to possess enough power to harm them.

Known Type of Forgotten
The basic forgotten possess superhuman capabilities, unnatural physiology, and powers beyond comprehension. The Six Crowned possess abilities far above any normal forgotten and it would most likely take a good majority of the executioners or several elite executioners to defeat a single Crowned Forgotten since these ones not only possess better abilities but also more intelligence being able to outwit their opponents to a degree.
 * -|Basic Forgotten=
 * -|Six Crowned=