Origin of Elves, Orcs, and Ghouls
NSFW Warning: Bestiality, Rape
In my world of Eo'rauk, Elves, Orcs, and Ghouls all have a common origin: Alps. The alps were created by the demon-god Skrael who forced a primitive human culture called the Alvors to mate both with himself and their own wolf-dogs. He would use magic to age up the offspring of these unions and make them mate with each other, continuing the process until he got the Alps. Alps possessed many of the features their descendants would bear, including the grace and beauty of the Elves, the savagery and brutality of the Orcs, and the bloodlust and hunger of the Ghouls. With these combined traits, they spread fear and terror across the land as they raped, murdered, and feasted upon all they came across. They preyed on many different folk, such as Dwarves, Gnomes, and Goblins, but their primary target was their own progenitors: the Alvors. They loved hunting them so much that they were to be wiped out if not for an intervention by the Fae.
On a late-spring day, a delegation of three Seelie Fae confronted the largest Alp clan and presented them with an ultimatum: renounce their treacherous ways and join them on the Isle of Greenhaven, or suffer the fate that use to befall their kin. While most laughed at this offer or tried to kill the Fae themselves (to no avail), there were some who took up this offer. Come nightfall, and the encampment of this Alpish clan began to howl and scream violetly. The bodies of those who had rejected the Fae began to twist and transform into what would become the Orcs. Meanwhile, the Alps loyalty to the Fae began to feel strange, as if they no longer needed rest. It turns out that they had turned into Elves, gaining everlasting life in the process. In a jealous rage, the Orcs began killing all the Elves in the encampment. However, a warrior band of Fae appeared out of thin air to rescue as many Elves as they could. Although they escaped fairly unharmed, the Fae warriors were only able to carry a few Elves away to Greenhaven, while the rest went into hiding.
After this initial conflict, many Orcs sought out the other Alps to get their help in slaughtering the Elves, but these Alps had suffered a face far worse than the Orcs. They had become Ghouls, gangly, raving beasts whose civility could only be temporarily restored by the consuming of blood, flesh, and bone. In their madness, they fought the Orcs and fled from them into deep mountainous caves and dark, wooded bogs.
Meanwhile, the Elves were developing into three distinct groups: High Elves, Wilder Elves, and Dark Elves. The High Elves were the ones who had been brought to Greenhaven by the Fae. They had developed the ability to emit a light from their bodies that shone bright and hot. They could concentrate this light into their hands, heating them up to the point that they could melt metal. They also began a tradition of scarring artistic symbols on their bodies. These raised marks could glow in the dark or be made to glow brighter by a High Elf as an attempt to show themselves off.
Wilder Elves were among those that were left behind on the mainland. They had the ability to touch a member of a plant network (a tree in a forest, a blade of grass in a field, etc.) and see through every member of that network, effectively using plants as spies. They became open to interactions with their former victims, being among the first Elves to have Half-Human hybrids by choice.
Dark Elves, however, were not so fortunate. The other elves that were left behind, they were seen with distrust, contempt, or straight-up hate by humanity. This is likely due to both their history and their ability to turn themselves and their possessions invisible. And while they did also gain Half-Elves among their numbers, this was mostly due to revenge rape by humans.
High Elves and Humans wouldn't have many interactions when a group of Humans called the Nolga ousted the Alvors from the mainland, sending them either south to unknown lands, or west to Greenhaven. This had happened centuries after the High Elves landed in Greenhaven, and in that time, they had gone through various migrations and wars with their Elven kin (primarily Wilder Elves with some Dark Elf populations) along with Firbolg and Trow, they grew distrustful of foreigners and only took them in as second-class citizens. However, after they worked to repel an Orcish invasion, the High Elves partitioned a majority of Greenhaven to the Alvors. This is because the High Elven population suffered tragically from this war, with them almost going extinct at the hands of the Orcs if not for the Alvors. This, along with the following migration of the Andors (those Alvors who fled to the south), caused the Alvors to coalesce from many scattered tribes to structured kingdoms.
While tensions between the various Elves and their former victims have gone down a lot by modern times, there are still some conflicts between them that still arise. However, Orcs and Ghouls are still very much in a fight against the Elves, although not as much with humans.
This is what I've got so far on the origins of Elves, Orcs, and Ghouls, be sure to ask questions if any of this information is unclear.