Nightmares: the monsters of the Netherworld.

N-Core/ Nightmare Core: stone-like heart used to bring power upon the Arma and Bestia.

Netherworld: the world where Nightmares reside.

Arma: a human who can turn into a weapon.

Bestia: a human who can turn into a beast spirit.

Handler: Either a weapon or a spirit handler.

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Class Rank: for people

E

D- skill

C

B- 2nd skill

A

S- 3rd skill

SS

SSS - 4th skill

Demigod

God- 5th skill

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Nightmares(incomplete)

Veloce: speed-type nightmare, the average size is one meter, have sharp claws which are used to kill their enemies. 

Forza: strength-type nightmare, the average size is two meters, have large shoulders, and tough to kill. 

Higante: giant nightmares, varied sizes but minimum 50 meters.

Tiratore: long-range nightmares. 

Uccelli: nightmares that had wings, they can fly, duh.

Enigma: a group of mysterious nightmares, hard to find, had bizarre powers.

Zviera: beast-like nightmares, walked on all fours, sometimes had wings. This type of nightmares is common in the Netherlands. They varied but most of them are close to an animal in terms of resemblance.  

Furfante: the most intelligent species of nightmares, their special features is that they had red eyes, horns, and long ears.

Pesce: nightmares that lived under the sea, they are elusive but dangerous, especially if you fight them in the water. 

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