So, a thing came up recently in my Wolf-packs and Winter Snow campaign. My players met a lich who was one of the ancient Morlocks; old enough that he remembered being a slave during the final days of the Serpent-Folk empire. I hinted at something I've decided as being canon for my own game; the Morlock slaves created their own gods as a weapon against the Serpent-Folk. The 'War In Heaven' between the Serpent-Folk and Morlock gods was responsible for their empire's fall.
For reference, I'd place the Serpent-Folk empire as first coming into existence 4 million years ago, during the late Pliocene. The Serpent-Folk may have existed for some time before that, but not in any significant form. They first began breeding Morlocks around 2.5 million years ago, from Homo Habilis, in the earliest days of the Pleistocene. The empire fell around .8 million years ago, during the mid-Pleistocene. Our lich, Abraxus, will have been alive at this time, making him around eight-hundred thousand years old.
Now, I portrayed Abraxus as being urbane, cultured and sophisticated. Although his technology level is still stone-age, his practice of magic is far in advance of anything his modern descendants the Morlocks, or their cousins the Humans and Neanderthals, are capable of. He describes these people as 'fallen from glory'. I think there may have been a civilisation populated by former slaves in the ruins of the Serpent-Folk empire, and that they were not the degenerate simpletons that the Morlocks of the 'modern' age are. Certainly, a lot of their magitech will have been scavanged, but they should have been capable of their own works, such as (for example) the creation of their own gods.
An idea occurred to me: what if these ancient Morlocks, rather than being inherently smarter and more civilized than their descendants, instead had ways to 'elevate' their own kind to a higher state? This, then, is where the idea of Eloi came from; the magical elites of Morlock society who have become post-human beings through a magical transformation. Here, then, is how I think this could be accomplished. It's only canonical in my own game, but feel free to include it in yours as well.
To become an Eloi requires a series of rituals, each of which brings the subject one step further down the path towards becoming an Eloi. Each step along the path must be taught to the Eloi-to-be, and requires a ceremony be performed with the mentor guiding them towards Eloi-hood. An undead Morlock can perform the rites, but will typically gain less benefit from them.
The process of becoming an Eloi causes a Morlock to neglect their physical prowess in order to focus on magical growth. As well as the listed effects below, the Eloi increases the attribute modifiers for all mental attributes (Intelligence, Wisdom and Charisma) by the number of rites they have completed. The actual score remains unchanged. Likewise, the modifiers for their physical attributes (Strength, Dexterity and Constitution) are lowered by the number of rites the Eloi has completed.
(So, for example, after completing the first step, an Eloi with 10 strength and 10 wisdom would have a strength penalty of -1, and a wisdom bonus of +1. These increase to -2 and +2 after the second rite, and so on.)
The First Rite
The first stage is, in many ways, the most significant; it is the point of no turning back where the Eloi commits to the path.
The first rite is very simple: the Eloi-to-be renounces mundane matters in pursuit of magical perfection. The rite consists of a dire oath to the mentor, ceremonially 'signed' by branding the mentor's palm-print over the Eloi-to-be's heart; to do this the mentor's hand will be coated in hot tar to allow their palm to scorch the Eloi-to-be's skin. This brand deals d4 damage to the flesh of each.
An Eloi who has completed the first rite has all the XP requirements to gain levels doubled. They understand that they will learn only slowly, and their minds no longer develop as normal. Instead, much of their advancement will come as steps down the path to Eloi-hood.
After completing the first rite, an Eloi no longer ages, although they will finally die of old age when their time comes. They become completely infertile. Although they can still catch diseases, they will never transmit them to others; they are never infectious.
After only the first rite, an Eloi cannot perform the rites to make another Morlock like themselves.
The Second Rite
The second rite expands the limits of the Eloi-to-be's mind, granting them a greater understanding of magic and breaking the curse of simple-mindedness bred into them.
This rite requires that the Eloi-to-be's mind be altered. To do this, the Eloi-to-be is rendered immobile or numb to pain, by the use of narcotic drugs. Using long, thin needles, the mentor drills a number of tiny holes in the Eloi-to-be's skull, into which a number of ritually prepared substances are inserted to unlock the magical potential of the Morlock brain. These substances are, in game terms, three magical reagents, each of them unique to the specific Eloi-to-be's anatomy. Determining which reagents will be required (and where they must be placed) requires several days of careful study on the part of the Eloi-to-be and their mentor.
Once completed, the second rite allows the Eloi to perform experimental magic. They can cast spells in unusual forms and research new spells; they have all the capabilities of a human magician. They can also, if they wish, record spells on a sanctum wall just like a human magician would. In addition, the Eloi gains an Art skill chance equal to their Perception skill chance.
Again, an Eloi cannot perform the second rite at this stage of initiation.
The Third Rite
The third rite is where the Eloi gains full understanding of their state. It is the tipping-point midway through their initiation, where they finally become more Eloi than Morlock.
The rite is more complex than those before. The Eloi-to-be must be brought into a hallucinatory state through the consumption of psychadelic substances. There, their mentor guides their visions carefully, pulling their gaze inwards. In order to truly unlock the potential in their genetics, the Eloi-to-be must open their 'third eye'. They direct the mentor to a particular spot on their forehead, and the mentor cuts away a flap of skin and then drills out a disk of bone. A single magical reagent (again uniquely chosen for each Eloi, as in the second rite) is placed in the new socket and covered again with skin to form a mystical third eye.
After completing the third rite, the Eloi can now mentor other Eloi-to-be through the first to third rites. They do not require a mentor for any further rites, instead instinctively understanding what they must do to achieve the next step on the path (but not what effect it will have on them).
In addition, the Eloi becomes innately aware of the state of their body. They can simply understand, through concentration, any diseases, injuries or disorders they are afflicted with, and the effects these have.
The Fourth Rite
The fourth rite cuts the Eloi off from the world around them. They renounce their former lives and become something other than mortal.
The rite is incredibly complex, requiring the Eloi to perform a ritual fast for three days before beginning. After a series of complex gestures and syllables, the Eloi must consume the heart of another Morlock, although it need not be fresh and the donor need not have been killed for this purpose. This is left to digest, and then ritually vomited up, symbolically purging their species from them.
After the fourth rite, the Eloi's heart can no longer be substituted for a magical reagent or sacrifice. Neither they nor their body can be used for magical reagents or sacrifices. A wendigo gains no benefit from consuming their flesh. Their material form loses its magical potency and their souls are of no interest to the gods and spirits; they are only vessels for the Eloi's magical nature. The Eloi will no longer die of old age.
The Fifth Rite
The fifth rite causes the Eloi's spirit to become seperate from their body, with only the most tenuous of links.
The rite must be performed alone and in total darkness. The Eloi must remove all tattoos, scars, and brands from their skin, flaying any bodily modifications down to the flesh. They must be left with no spells recorded on their skin, and no marks of the previous rites. Each spell deals 1 point of damage to flesh when removed. The Eloi can spend as long as they wish to complete this rite, but once begun it must be completed in a single attempt. If the Eloi enters light or the company of another person before it is completed, then the fifth rite, and any subsequent ones, are forever cut off to them.
After completing the fifth rite, the Eloi no longer requires food, water, sleep, or air. They do not feel pain. They merely exist, without requiring any external support.
After the rite is performed, the Eloi can re-record any spells they wish into their flesh.
The Sixth Rite
The sixth rite is the final rite in the process. Unlike those before it, it does not merely affect the Eloi themselves, but all Morlocks in the world. It is unknown if it will also affect other hominid species.
Completing the Sixth Rite requires many hundreds of mortal lifetimes, and is incredibly complex. The ritual's requirements include, but are not limited to the following:
-All the Serpent-Folk must be killed with no chance of returning.
-All the Serpent-folk's gods must be destroyed completely and permenantly.
-A number of complex geomantic monuments must be placed around the planet to extend the rite's effect.
-At least one Serpent-Folk (alive, undead, in an embryonic state or otherwise) must be ritually sacrificed for every Morlock that has ever been born. This is probably best achieved through the rapid mass production of embryonic Serpent-Folk that are killed in huge numbers before reaching maturity.
-The Eloi performing the rite must truly die at least once. Unless this is the final step they perform, they had better have a way to return from it (most likely as an undead being) afterwards.
At least one Eloi - the Lich known as Abraxus - is currently working on completing the sixth rite, and has been doing so for several thousand years. It is unknown if he has assistance from other Eloi in this endeavour.
It is unknown what the completion of the sixth rite will actually do. Abraxus, in his transcendent madness, believes that it will free all Morlocks and their descendants from the shackles of mortality.
The sixth rite is not a practical goal for PCs to pursue over the course of a campaign; the scope and wide-ranging effects of it are far beyond what can be modelled in a table-top session. Instead, the pursuit of the sixth rite is a plot device, driving the actions of NPCs. It is possible that an Eloi pursuing the sixth rite could become a 'patron' of low-level PCs, setting them quests that help towards their completion of some step of the sixth rite.
Non-Morlock PCs might be able to perform and benefit from the rites. In my campaign, they cannot, but variant versions for each other species can be developed. The effects of these rites are broadly (but not totally) similar, and can only be performed by human Magicians and Mystics, or by Neanderthal Apothecaries. Where for Morlocks, the rites rely on body modification, for humans the rites require the creation of magical artefacts and monuments, whilst for Neanderthals the rites require the use of alchemy.