Where the Elves Go

There aren't very many high elves in Centerra.  This is because Centerra is small and boring and it is impossible to do anything of any consequence there.  They leave for the same reason that people leave the small, bucolic towns of their youth.

The only folk left behind are their simple, impoverished cousins, the low elves (which is the only kind of elf that most people know of).

Where do they go?

Well, some go into space.  Head out far enough and you'll be sailing across the Astral Sea, bound for much more interesting destinations.

The Astral Sea

You can escape the planet's gravity well with a wizard rocket, by catching the Cat's Tail (a space elevator that dangles across the sky sometimes), or by walking to the moon.

Once you get past the orbital habitats you'll hit the astral sea.  You'll need a ship for that.

The surface of the astral sea is just a gravity plane.  If you drop an item off the side of your ship, it'll fall down to the level of the astral sea and just bob there.  There is usually air there.  Sailing on the astral sea is actually easier than sailing on the ocean, since your ship doesn't even have to be sea-worthy.  It just has to have mass.  You could sail on a boulder (and people do).

If you roll your ship hard enough, you'll roll it upside down.  You can sail upside down just fine.  In fact, a lot of astral ships have another upside-down ship on the bottom of them, like a ship sailing across the surface of a mirror.

The only expensive piece of equipment you need to sail on the astral sea is astral sails.  These are differently colored sails that are attracted or repulsed the light of certain, known stars.  There is wind in space, but sailing by starlight is more reliable.

As far as I've described, the astral sea is flat--a plane that the solar system floats through.  But farther out, the topology becomes more complicated.  Like space itself, the astral sea is only locally flat.

Farther out, it wrinkles into ridges and walls, holes and pillars.  You may find yourself sailing up a pillar of astral ocean in your journey to an astral "ceiling" a million miles above you.

It frequently resembles sailing across the surface of a very complicated spider's web.

pictured: the surface of the astral sea, the astral weave

sailors in space often pray to lolth

Of course, not everyone in space cares about the astral sea.  (See also: liches in their airless, flying ziggurats, or asteroid golems and their attendant homunculi.)

Temporal Kingdoms of the Elf Lords

Centerra is a filthy backwater.  The elves would go into the past, before it was all ruined, except that the past is full of fucking dinosaurs chewing up the time line, and the past is ruined, too.

There is a hour and a date.  It is in our future.  And when we reach it, a million million elves will materialize and kill everybody.  We don't know exactly how, because the event is not survivable.

And then the elves set up their temporal kingdoms, which extend not across space, but across time.

The mightest elven kingdoms last millenia, sculpted subrealities designed for a particular vanity project.

The smallest elven kingdoms might only last for a single morning, or the time between sunset and night.

There's a million million elves, but it's really just one elf.  How?  Just go back 60 seconds back in time, stop yourself from going in that time machine, and then the two of you go back 61 seconds in time.  Repeat until you have enough copies of yourself to make an army.

That's actually a good description of what a temporal kingdom is like.  The same one or three elves, looped over each other continually and infinitely until the entire universe is populated with them.  They are all immortal, and so every elf you see is just a different elf in a different stage of their life.

The servant elf is the same as his master, only a trillion years younger.  (Because of time loops, nearly all of the elf lords are many times over than the universe.)  Or perhaps the elf being tortured is the same elf, 600 years younger, being punished by her older self for her youthful indiscretions.

And the elf mason who builds the castle is the same as the master of the castle, already moving into the finished rooms.  She just has to spend another millenia building the castle before she can enjoy it herself.

There are schedules.  Moons are replaced with clocks.  Numbers are tattooed so that everyone can keep track of everyone.  Memories are wiped, simulated, and restored.

And of course, if you ever kill one, you upset this entire teakettle of a timeline.  Even interacting with one is dangerous, since it forces the entire universe to reset it's causality every time something is substantially touched.

Fighting a temporal elf-lord is a lot like rerolling the encounter every round.  Kingdoms rise and fall outside the window.  The sun cracks, vanishes, and is replaced with a golden, lobotomized mega-elf.  Your opponent becomes old, then young, then a trio of gender-swapped clones.  The walls swim and decay.

And if you ever kill the elf-lord, the kingdom vanishes, because it was never visited by its builder.  The land is untouched, and the castles (the mile-high crystal spires with literal stars caged in their minarets) are gone.  And you have only seconds before the adjacent temporal kingdoms take notice, and their timelines come rushing in.

magnified a millionfold
as if god was a narcissist obsessed with beauty and novelty