The inevitable eternal slumber that is the fate of all High Elves
Transmission & Vectors
The Earthslumber is not a disease, nor a curse, nor a malady or ailment...it is an ineffable part of High Elven physiology born from the shard of primordial creation each carries within them, and both a consequence and burden of those who possess eternal life. There is no escaping it, or running from it, and the only way to stave it off is to wander, explore, and to continue the inexorable march onward...though one day, all creatures, no matter how long lived, are fated to enter The Earthslumber...once they have seen all there is to see, and viewed all they could.
The cause of The Earthslumber is simple, yet complicated...easy, yet hard, and understandable and ineffable. It is contradictory, and can differ from creature to creature...but at its most basic level, The Earthslumber is caused when a High Elf loses interest in the world at large, having lived so long and so many lives across so many eons that they grow apathetic, bored, or simply grow tired with life. It can also onset early if a High Elf grows used to a routine, settles down, or stops seeking "new" experiences, memories, scenery, people, places, and more.
A hardening of the skin, apathy, torpor, laziness, and similar symptoms are all signs of its onset. Once it has taken root, it could take anywhere between years, decades, and even centuries to fully transform the given high elf depending on how languid they have become, and on a number of random other variables, though once begun the process is nearly irreversible unless action is taken immediately and drastically the moment the symptoms appear...though with each time they appear, they will begin to onset quicker and quicker.
There is no treating The Earthslumber. Once it has taken root, the process is all but inevitable unless the affected takes great care to change their scenery, lives, and mindset in a dramatic and often heartbreaking way. Once it has taken root, it could take anywhere between years, decades, and even centuries to fully transform the given high elf depending on how languid they have become, though once begun the process is nearly irreversible unless action is taken immediately and drastically the moment the symptoms appear...though with each time they appear, they will begin to onset quicker and quicker.
The only way to prevent the onset of The Earthslumber is to explore, investigate, to move ever onwards and to never let oneself become stagnant or used to a routine. New experiences, new lives, new people, and new things must be sought always and constantly, and wandering must be one's motto...mere obsession with one subject is rarely sufficient to prevent it's onset, as simply studying the same topic in the same scenery will only hasten its onset. One must constantly seek the new, forget the old, and move on to stave it off.
In their endless years of life, some High Elves lose themselves in introspection, hopelessness, apathy, or languid torpor, and can no longer rouse themselves to face the endless march of days. Still others simply lose the drive to explore, or the spark that once made them so vibrant and curious, and begin the slow decay into inactivity as they lose the will continue on, having lost interest in the Planescape at large. Others, in a bid to continue their explorations, divine a means to cast their consciousness far from their bodies, wandering planes and realities far beyond mortal ken. Absent the vitality of the soul, a high elf’s physical form succumbs to decay over the centuries. In time, as their bodies languish in inactivity and decay without or without their soul, their bodies begin a slow and painless transformation into a more natural form of life as their bodies are absorbed by their surroundings to become a part of the natural cycle. The bodies of these High Elves always invariably become some key and important part of the landscape or ecosystem their bodies fell into The Earthsleep within, and the stronger the High Elf was in life, the more towering and monolithic the shape their bodies take once they fall victim to The Earthsleep. Doomed to an eternal rest from which there is no waking, High Elves, if they did not already cast their soul from their bodies, find their soul passing on as their bodies began the transformation process...things such as towering Dire Oak trees, massive underwater coral reefs, hills or rocky cliffs, clouds and vapor, desert oasises, and even fonts of primordial elements are not uncommon, with the thing formed from them growing larger and more beautiful the stronger they were in life. Often, the things formed from the bodies of slumbering High Elves retain a shard of their primordial spirit, often becoming semi-sentient or sometimes possessing magical qualities...oftentimes, they bring great bounty to the nearby land and bless those who live there for eons to come. Rumors persist among the most ancient Elven scholars that the Earthslumber was not a natural affliction originally, however...that the Yema, the New Gods, created it and forced it upon the Sapphire Elves shortly before stripping them of their powers and unity, turning them into the lesser High Elves as a means of ensuring that the High Elves could never against unite against them like their ancestors the Sapphire Elves could.
All High Elves know of The Earthslumber, though few truly fear it. They see it as a natural return to the Planescape that gave them their immortal lives, and a natural part of the cycle of all things. To fall into The Earthslumber is seen as the natural end for all High Elves, and after eons of life many come to embrace it as a rest from their lives of constant hustle, bustle, and a chance to finally reunite with those of their kin already passed. Many Elves and High Elven cultures alike see The Earthslumber as a comfortable reward for those who have lived a long life, and speak of their allies, family, and friends that have "entered The Earthslumber" with great reverence. Often, pilgrimages are undertaken by those who knew them in life or those who revere them, whether to try and commune with some small piece of their former consciousness or to simply visit the site of their transformation...likewise, to disturb the site of a High Elf's Earthslumber is an act most assured to cause universal hatred for the offending party, and one assured to provoke the Ire of all Elvenkind.