Earth, sol III, the blue earth, the only planet were life exists, a common kind of world, one usually lacking of magic or such energies or with inhabitants unable to harvest it, humans are the only sapient species in these kinds of worlds.
They reign supreme in these worlds, even when another species exist that hunts them down or rival's them, they stand on top, in those versions of the earth, most humans hav no idea that such things even exist even if their impact is clear to see.
In one of these worlds, one with beings known as anomalies, something that wasn't an actual anomaly appeared, in the darkness of a sewer, it manifested but instead of simply appearing, it took notice of the corpse of a human, still fairly fresh.
He must have been disposed of recently, if the authorities were to be called soon, it was certain that they would find it, it wasn't much hidden and the sewer were an obvious place to search, especially when cameras monitored the streets.
The thing chose to not appear like many of its counterparts and instead incarnated with the corpse, an action that warranted nothing and wasn't quite sensical but as it did so, the corpse sprung in its feet, the corpse of the man was no longer dead and it was no longer the man's body.
The body twitched uncontrollably, bubbling, extending and shifting its shape in an archaic manner, the being stumbled for a while ripping its clothes off.
After a little while, the convulsions stopped and the newly arrived being took a look at itself in the dirty water, it saw that it had the proportions of a human, bulkier than most but nothing that could warrant suspicion, its face was blank and it had no hair.
'I'll simply take the appearance of that one...' thought the being was the usual features of a human appeared on its head, slicked back hair, deep purple eyes, a nose and a mouth filled with pristine white teeth.
The being had chosen to take on the appearance of a certain someone, someone who wasn't even part of this world, how it had come to know the appearance of that man was unknown.
It smiled maniacally at its own reflection, as it made clothe manifest to cover its body.
In the dead of the night, seeing a man dressed in a magnificent dark three-piece suit, dressed like a rich business man coming out of the sewer was a bizarre sight.
The man brushed his shoulder, pulled on his leather gloves and reajusted its glasses befor turning to the curious onlooker who was so enthralled by the vision in front of him to react much.
"Well, well... I thought anomalies were supposed to be invinsible to people, do I not get the perks?" spoke the man as he started walking toward the onlooker.
"Hey kid, ever seen some ghosts?" questionned the man as lean forward to meet with his interlocutor eyes, making a big and beautiful smile.
"Yeah but everyone says that I am just imagining things" responded the child, who should by all means not be out in the city by this late hour and also not speal to a stranger.
"I see then, that's unfortunate" retorted the man absentmindedly before putting his gloved hand on the child's head.
"I think it's time for you to go" he then said before a loud splashing sound was heard.
As the man casually strolled away, all that was left behind was large amount of blood having covered the wall behind were the child had stood.
Only the man's low chuckle was heard in the silent streets.
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As expected, normal humans couldn't see him at all, he could kill someone right there and no one would have any idea what happened.
'There are more of those anomalies walking around than I would have thought' thought the man as he watched around, anomalies crawled on the buildings and zig zagged through the passersby.
Why they wouldn't attack any human was hard to understand, anomalies grew by slaugthering humans and it wasn't like anyone was around to stop them if they did, especially when considering the fact that they lack in intelligence, their choice to lay low was nonsensical.
No one had come to stop him when he had turned this kid into a mural, so why would someone stop them?
The man entered a school, this place reeked of despair, a beautiful scent that attracted anomalies, he then visited other parts of the city but still nothing of great interest was to be found.
"Well I guess there is no choice then" he said outloud, the humans walking around couldn't hear him but the nearby anomalies did and scuttered away.
He grabbed the closest human's head and they barely registered that something had stopped them in their track that their head were turned into nothing but blood, the people around barely noticed their heads suddenly growing in size before they were covered in the blood.
The man looked at his hands with a questionning gaze.
"Well, human spirit sure is strong, I can't help but find joy in the slaughter of these people for no real reason" he spoke as he smiled in depraved way as he went on to pop heads as of they were balloons.
By the end of his slaughter everyone had either fled or had been converted into fertilizer, no blood had stained the man's clothe at all, he simply stood in the middle of this carnage and smiled lightly with satisfaction.
"This may be fun but I doubt I will kill this world by just blowing some human heads left and right, what could I do to accelerate the process?" wondered the man out loud as he sat on a bench, not minding the headless corpse beside him.
The man noticed the approach of some people with energy similar to that of anomalies, one side of him wanted to test himself against them but one should first try out against a smaller and singular fish.
He walked away, disappearing through a wall right before he could be seen.