Nyx

Nyx is a god of death the literal essence and concept of death. The true form of Nyx is isolated from the world inside its own realm, the only way for it to communicate is through an Avatar of Death or The Fall.

Plot
Nyx first appeared when The Fall was provoked in The Root, affecting Tael Lightwing, Ienzo Korff, Excellion, Kosmos, Yonio Antonio and pretty much every living being in the world.

However The Fall failed for some reason and Nyx entered plan B, to erase people's will to live in order to fully accomplish its goal.

All living beings' lives were completely changed and their memories blocked and replaced by sad and depressing ones, somehow the main characters at the time managed to get their memories back (though Excellion apparently hadn't lost any memories) and stood up against Nyx.

The main characters got stomped, Tael got scarred by hellblaze and received a cauterized wound that may never heal, and one of the regalia users had to sacrifice themselves in order to seal The Fall and mend reality.

True immortality
Nyx can indeed not die, if death ceased to exist then the concept of death would also stop being, in which case it can't die, its a paradox.

Avatar
The avatar version of Nyx is a really tall and heavy entity that uses a broadsword and an unknown set of spells.

Bane of the immortal
Nyx can completely destroy immortals through the use of skills derived from this passive like hellblaze.

Emotion Breaker
Nyx can use this psych to disable the creation of feelings in a body.

Hellblaze
A skill derived from Bane of the immortal, it creates a swarm of black fire with several uses like enchanting weapons, acting as a persecuting projectile, and just launching waves of it around.

Deathly Paradox
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