"For thousands of years, the Tablelands have remained untouched: its politics frozen in a delicate stalemate, its life in a balance even more delicate. It is true that the Dragon Kings amused themselves with their petty wars, rattling sabers to punctuate the passing of ages. It is true that, occasionally, another city would be swallowed by the wastes.
But there were no surprises. The Dragon Kings steered everything from their omnipotent perches, content in their superiority, but ever thirsting for challenge. All that has changed. The Tablelands have been thrown into turmoil, the likes of which have not been seen since times forgotten. The Dragon Kings have been thrown into confusion, grasping for the tedium they so recently lamented.
And yet I fear the worst is yet to come. Change is in the air, and change has never come gently to Athas."
- – Oronis, sorcerer‐king of Kurn
Dark Sun is a campaign setting made for AD&D 2nd edition back in '90; there are 3e conversions approved by WotC, but we had to wait until 2010 and 4e for an updated official version. Dark Sun is essentially a grimdark post-apocalyptic mix of D&D, Edgar Rice Burrough's Mars series, and Dune; it's pretty awesome, but immediately proceeds to eschew common sense (unlike Dune).
The game is set in the world of Athas, a dying planet. Once full of happiness and sunshine, the planet was drained of all resources during the long and rich history the creators came up with. There is no water, no minerals, and no hope: only cannibal halflings, a lot of sand and a dying sun.
The world is so fucked up it makes Mad Max's setting look like a hippie paradise. Kinda looks like Barsoom on massive grimdark crack. Everyone wears Female Fantasy Armor (yes, even the dudes), and according to the developers, this was the entire reason they picked a hot climate for the setting instead of an icy one, despite the fact that wearing Female Fantasy Armor in the desert would result in a quick death from sunstroke and dehydration; if they wanted everyone to wear Female Fantasy Armor then a hot and humid environment like a jungle or a tropical place, such as the setting for the comics series Shanna the She-Devil, is the ideal choice (less clothes keeps you cool when it's hot and humid, means less things to get caught in foliage or get pulled by predators or rivals). The only few realms remaining are fascist police city-states ruled by wizards (all of them varying shades of evil) whose environmentally-unfriendly magic is responsible for fucking up the planet in the first place, and who're slowly losing their humanity as they turn more and more into dragons. Beyond civilized lands everything eats everything. The best weapon you can find is the femur of your party's cleric after being eaten by something that looked like a rock and the best armor is mostly the remains of a giant cockroach. There are no gnomes, orcs, kobolds, or furries because all of them were exterminated by some jerks with psychic brains and magic hands. They were the Champions of Rajaat, and they and the Sorcerer-Kings are by-and-large one-and-the-same.
The original Dark Sun setting got pretty harshly wrecked by advancing novel continuity. Once a buncha tie-in protagonists have already killed all the iconic villains and started fixing the setting's problems, what's there left for you to do? In response, 4e went full-reboot and adopted an Eberron-style anti-continuity system: every campaign begins in exactly the same time and place, and the story never advances. It was, especially for a 4e idea, incredibly well-received, and will probably carry over into any attempts to adapt the setting for 5e.
Thus far, the closest Wizards of the Coast has come to actually adapting the setting over to 5e is a few ideas about how to change over any adventuring paths to Athas, though the design team has repeatedly mentioned they intend to try in the future. Co-creator of 5th Edition and creative lead designer Mike Mearls has stated that he's pretty much converted Dark Sun to 5th, even if only for an office campaign.
Most of the less-popular generic fantasy races were exterminated a long time ago, good riddance! This means no gnomes! First reason why this setting is full of win and awesome.
- Aarakocra - Sentient vultures, for those who don't want to play anything normal, but hate bugs or lizards.
- Dray - Horribly deformed dragon-people. Basically a failed magic experiment. Created by Dregoth, the undead Dragon King. Later generations were less-mutated. 4e made them straight-up dragonborn.
- Dwarf - Almost typical dorfs, except taller, waaay more muscular, bald with Klingon-like head plates and are even more fixated on their stuff than the hairier, stuntier variety. So fixated, in fact, that if they died without completing the shit they were obsessing over, they came back from the dead as banshees (sentient zombies that looked like a dwarf without skin).
- Eladrin - Added in 4e, the dwindling remnants of the race that once ruled the Feywild, which on Athas has literally dissolved into nothing, leaving only a scattering of extradimensional oases as a result of defiling.
- Elan - An experiment in creating human uber-psychics by a psionicist order that went wrong due to being too powerful
- Elf - No forests for them, ha! They are desert nomads, thieving and griefing all the time. Finally, straight players can consider playing an elf.
- Gith - Descendants of a contingent of Githyanki that came to Athas generations ago and became stuck, unable to leave. As a race inherently strong in psionics, they are feared opponents and gladiators, but are still often employed as slaves, which is funny, because they always end up like that, but this time without Illithids.
- Genasi - Only present in the 4e version. They claim they were originally set up as rulers over Athas by the Primordials once they killed all of the gods... but they became decadent and indolent, so the other races drove them off the thrones. And then they blew Athas all to fuck, which the genasi are still gloating about. Now they're starting to emerge from the wastes because they believe it's their job to take command again and fix this shit. Known subraces: Earth, Fire, Wind, Ember, Magma, Sand and Sun.
- Half-Giant - Big bad meanies, with a lolrandom alignment. Usually really fucking stupid.
- Halfling - Cannibals who live in the remaining strips of forest. Despite Denning's initial fuckup in The Verdant Passage, where he has the dragonfly riding midgets flinging spells hither and thither, no they cannot use arcane magic. Tries to retcon this in The Cerulean Storm but it doesn't quite work. MAJOR PLOT LOOPHOLE. Actually (spoilers!) the origin of all other demi-human races on Athas, as theirs was the high civilization of the Blue Age.
- Human - Sentient halfling, only larger. Always average, always racist. Just like in real life, the race arguably responsible for fucking up the planet. Somehow still manage to be the norm, large and in charge.
- Kenku - I shit you not. These crow-like humanoids are mentioned as existing as a viable race (with an accompanying language), but is then promptly forgotten and never mentioned again, so most people never think of them in the context of Dark Sun.
- Maenad - Alien berserker-psion emos that Andropinus recruited from somewhere beyond "The Black", then turned loose to die in the wasteland after they helped him get his city-state back. Rather pissed at that.
- Mul - Half-dwarf! Second reason why this setting is full of win and awesome! Bred for size and strength, but without the lack of agility of the typical stunty dorf, no slave was worth more than a Mul. Except a better Mul. Very prized as gladiators. Suck it, Russell Crowe. Unfortunately, like real-life hybrids tend to be, Muls are sterile, and they also tend to be born into slavery and kill their mums on the way out.
- Pterran - Pterodactyl-man shamanistic retards that remind you of a certain cheesy villain from the X-Men comic books.
- Ssurran - 2-legged sentient komodo dragons. Lives in the desert and loves them some lava. Very resistant towards heat and the Dark Sun, these guys enjoy worshiping Fire and Magma.
- Tarek - Earth-worshipping, hulking, ape-like humanoids from the mountains. Pretty obvious an "evolved" strain of Athasian Orcs, like how Ssurrans are Athasian lizardfolk. Take obvious inspiration from the ape-men of popular pulp novels and Frazetta/Vallejo paintings the same way the rest of the setting does.
- Tiefling - Another 4e addition, brutal raiders from the most hostile and barren regions of the desert, descendants of people who turned to fiend-worship for the strength to survive in the wasteland.
- Thri-kreen - Sentient mantis. Strange, scary folk who can only communicate via their own language or telepathy. Like their elves raw. With four wickedly clawed arms, these guys can fuck shit up.
- Yuan-ti - Much like the kenku, the classic yuan-ti are only technically part of the setting, and seem to have been largely forgotten the second after the core setting material was published, despite featuring prominently in the Dark Sun CRPG Wake of the Ravager, a game nobody remembered until GOG.com began selling many (most?) of the SSI AD&D modules of the 80s and 90s. Now that WotR is readily available, the thing people remember most about that game is the numerous, game-breaking bugs. (But you should still buy it, as workarounds to the bugs do exist.)
- Pyreen - A non-player (though 4e made them an epic destiny) race of ancient guardians from before the world was burned to shit, Rajaat was one of these guys before he went screaming off the deep end. Looks like a prettier version of how 3.5's Mongrelfolk are supposed to look based on fluff; a harmonious blending of human, halfling, dwarf and elf. This mysterious & mystical mongrelfolk nature is strange, considering that halflings were the original inhabitants, and it also ignores several now-extinct but previously prominent (or at least "normal" non-monstrous) races, such as orcs. Epic-level immortal multiclassed druid/psions attempting to fix the world. Not getting very far.
- Athasian Dragon - Only "playable" by a very technical definition of the term, since it was an epic-level class for level 21+ characters with nastily-difficult requirements, though 4e made it an epic destiny. Not at all like the normal D&D variety, which don't exist on Athas, Athasian Dragons are horrible monsters that embody the corrupted nature of arcane magic in the setting: rapacious, violent, and filled with rage and a lust to dominate or destroy. Depending on source, there's either many or only one being that has ever successfully completed the transformation, and he's the other BBEG of the setting, as mentioned above, but almost all of the Sorcerer-Kings are at least part of the way there.
- Avangion - The opposite version of an Athusian dragon, being the life-nurturing embodiment of what arcane magic should be. Looks like a bizarre glowing manta ray-dragonfly, with a huge wingspan. Not as much balls-out murder power as a dragon, but able to no-sell many of its abilities, actually support its party, and not be an insane rage-cauldron the DM could take over whenever he felt like it. Just as hard to qualify for though, and also a 4e epic destiny. No one in the Tyr region has ever successfully become one, though one NPC as far down the process as most of the Sorcerer-Kings are to being dragons, and unlike many of them is actively trying to advance.
- Clerics - There are no real gods in the setting (according to 4e, this is because the Primordials drove them off in the Dawn War), so most clerics worship elements or quasi-elements. In a desert world, summoning water elementals will get you pussy until you realize that if you level up to much you become a true elemental too. Very nasty to be drank alive for being a water elemental. The way they are described, they are more "elemental shamans" than archetypical clerics. Other types are insinuated to exist, such as a 'sun cleric' featured in the novels, representing the aspect and domain of the sun as a natural force rather than a deity.
- Druids - Druids serve spirits of the land. They have a guarded lands that they are responsible to look after.
- Gladiators - You know. Like the movie. Also one of the most overpowered classes in the times of AD&D, a low level gladiator could be the personification of a certain Frank Frazzeta illustration entitled "The Destroyer". Essentially, they were Barbarians before Barbarians as 3e made them were a thing.
- Dune Traders - lol that's actually a class? Was more one the role-playing side of things, could get loads of handy contacts and power within tradehouses. Took care of diplomacy, trading, and generally any situation that could be resolved without a weapon.
- Fighters - Not as good as a Gladiator in personal combat, but who is? Really excelled at attracting and leading armies at higher levels.
- Bards - Most bards sing songs and boost the other party members' rolls. Dark Sun bards will poison and kill you, and maybe fuck you. Maybe in that order, too.
- Paladins - lol nope. Honor and virtue fell by the wayside a long time ago on Athas, but what else would you expect from a planet this Darwinian?
- Templars - Replace Paladins thematically, but more on the police side of things to the point they are essentially the Sorcerer-Kings's Gestapo. Ability-wise, they're more like Clerics with slower spell-progression but more spellslots and the ability to use any weapon. Worship the Sorcerer King who rules their city.
- Psionicists - Psionicists are considered accepted and normal in this setting. In fact, every PC is guaranteed to have at least one psionic power! OMGWTF! Think Jedis, kind of. Wanna move shit with your mind without casting a spell like some faggy ass wizard? Check. Mindrape? Check. Fucking Time Travel? Double Check. Unfortunately suffered from the fact that psionics in 2e were a horrible mess, and with a few notable exceptions, most of your powers are either incredibly niche or use clunky subsystems.
- Rangers - Same old shit. Think Aragorn in the desert.
- Rogues - Pretty similar to the non-Athasian kind. Attracted a Patron at level 10, aka you work for me now bitch.
- Wizards - Two types exist in the setting, but everyone hates them both:
- Defiler - Evil mages, who suck out the life force of things. When they level up enough, they usually have an allergic reaction called dragon metamorphosis.
- Preserver - Mages who are not manly enough to steal life force, so they sacrifice efficiency to keep the stuff around them alive. Unfortunately for them, the commoners think all wizards are the same. Fortunately for them, most of their shit can be passed off as psionics. When they grow up enough to be considered bad ass they turn into the manta ray like aliens from Abyss.
Sorcerer Kings were the jerks chosen by Rajaat with the deepest reservoirs of hatred (read:racists) for everything. Except halflings. Or was it humans. SPOILER! These were usually the big bad dudes that Dark Sun campaigns revolved around killing. Unfortunately, author Troy Denning killed off most of them in the series The Prism Pentad, thus giving the campaign setting nothing left to live for. TSR brought out a small post-novel supplement entitled "Beyond the Prism Pentad", which also included references to a product called "Dark Sun: A New Age" that was never released, to try and save what little scraps of the setting was left after Denning's royal buttfuck of it all. It didn't work. As a result TSR brought it out back and shot it while you cried in your mother's arms.
Most/all Sorcerer-kings were/are in various stages of Dragon metamorphosis, i.e. turning into a Dragon, you idiot, as a result of their addiction to Defiling. "Real" dragons don't exist on Athas, and only the most powerful Wizard/Psionicists with the help of handy forbidden lore could start on this journey to REAL ULTIMATE POWER. Side effects include deepening of voice, a bad case of scaly skin, and the desire to FUCKING KILL EVERYTHING. Which gave rise to the most common-sense Dark Sun rule ever, via the rulebook Dragonkings, where a 25th level Dragon, if you were lucky/good enough to make it that far and survive a series of spells that had an outright chance to kill you, WAS COMPLETELY TAKEN OVER BY THE DM UNTIL LEVEL 30. How fun is that shit. The reasoning being the Dragon entered a period of Animalistic Rage. And of course only the DM could properly portray that shit, moron. Go sit on the couch and shut up. (Granted, it was better than giving players literal dragon-god-like power, give the tendencies of the sorts of player willing to commit the atrocities necessary to become a dragon to steal, fuck and kill everything they see including their fellow PCs.)
Originally, just one of the Dragon-Kings was an actual dragon, formerly Borys of Ur-Draxa. Fighting him was detailed in what was generally agreed to be the single hardest module ever made, The Valley of Dust and Fire. Don't try it, the weather'll kill you before you get thirty miles from the place, not to mention that the module pretty much specifically states that the players should not be able to kill the dragon; it details its stats and even says that if players are using the "Dragon Kings" supplement and are level 21+, they might mechanically be able to best it in combat, however, the dragon has prepared so many fucking escape-routes (including several teleporters that could be used at-will) that even if you were capable of doing so, the Dragon would escape the instant it realized it risked losing. Wonder how those "Prism Pentad" dipshits managed it... Especially since not a single one of them were even level 20 (their stats are given in "Beyond the Prism Pentad") , much less a full 5-man party of level 21+ characters.
To expand their use as a plot device, each Sorcerer-King/Queen ruled a City-State, up until they were slain by Denning like it was a bodily function:
- Abalach-re - The queen bitch of the City-State of Raam, this paranoid schizo cunt makes your average Skaven look like Ghandi. Also universally loathed and held in contempt by both her own people and all the other Sorcerer Kings. Whether her neurotic paranoia is the result or the cause of this is a bit of a chicken-or-egg question.
- Andropinis - He had egg shaped nostrils. He wore a toga and ruled over the Greek inspired City-State of Balic. Unique for being the only Lawful Neutral sorcerer-king (All the others are listed as Lawful Evil, naturally), and for running a state that actually somewhat functions, in a democracy-turned-dictatorial-sham kind of way.
- Hamanu - Mr. Lionface. Not one of the original 13 Champions, he was the ruler of Urik and a blatant homage to Hammurabi. Evil and cruel, with his draconic transformation halted rather than reversed, but his devotion to order, justice, rationality, and his father's dream of a green and peaceful land make him one of the best of a terrible lot.
- Kalak - You know your old, shriveled, power-hungry, slave-master of a grandfather? That's this guy. Ruler of Tyr before his plan to get jacked up quick on dragonsauce was discovered and foiled by a bunch of meddling kids and one talking dog. The 4e reboot explicitly starts every game with him being overthrown and Tyr being established as a Free City, before letting the PCs see where things go from there.
- Kalid-Ma - Former Sorcerer-King of Kalidnay, currently trapped in a near-death coma in a completely different campaign setting thanks to his head honchessa's cruel betrayal of everything good in her life in favor of her freaky, possessive stalker crush on him. Probably not coming back, regardless of what the deluded cultists rifling through his garbage think.
- Lalali-Puy - The hottest Sorcerer-Queen, and ruler of the barely civilized Jungle-Town of Gulg. Also one of the less-evil Sorcerer Kings by virtue of not doing much to actively hurt the people who adore her, with some liner notes specifically calling her the most likely King to make a face turn who hasn't already, though her current rule over Gulg is cemented by brutal enslavement of nature spirits, one of whom she's masquerading as.
- Nibenay - Called the Shadow King. Either he really, really hated people and being seen, or he was too stupid to cast a simple glamour to NOT MAKE HIM LOOK LIKE A DRAGON around his superstitious subjects. Ruler of the largest City-State of the same name, which was locked in a perpetual war with Gulg for some crazy strong blue balls. Or blue wood. Whatever. His templars are all female, and are forced to mate with him for the job, which is frankly par for the course for evil at this point. Even considering his hideous, part-dragon/part-man appearance.
- Tectuktitlay - He's a ladykiller, he'll rip your heart out and throw it down the fucking ziggurat. Bird like in appearance, he was the Aztec inspired ruler of Drag. Drek. Er, Draj. Smart, despite his insanity and cruelty.
- Oronis - Former Sorcerer-King of Kurn. Kinda. Oronis is a special case. He started to feel bad about... you know exterminating all the lizard-men, especially when he saw that it was all for a lie, and he and his comrades were turning the world into a ruin rather than a paradise. So, he took his vitamins, drank his milk, and managed to put the brakes on the whole "morph into a dragon through genocide" thing... and go the other direction into becoming an avangion. Kurn is dying, but it's just a facade for New Kurn now anyway, and he's withdrawn from politics to pursue further experiments into avangion-hood while leaving behind a "true" democracy. Literally the only Sorcerer-King actively trying to make his shithole of a world a better place.
- Daskinor - Kim Jong Il's Dark Sun doppelganger. Ruler of Eldaarich, this
paranoid asshatomnipotent and benevolent God King keeps his city on permanent lockdownsafe and protected from all the evils of Athas. Literally built massive walls to close off his city from the outside world thanks to his insanity starting to leak into the city as a wholebecause it is totally self-sufficient and wants for nothing the outside world has to offer. Especially not water and food.
- Dregoth - The undead dragon sorcerer-king, ruler of Giustenal. This dude got ganked by a bunch of the other Sorcerer-Kings who were tired of him bragging about the size of his
cockbook of spells a couple thousand years ago, but his loyal Templars brought him back as a Lich, and he's just been chilling underground unbeknownst to every else, for quite some time now. Created the dray race, which he hopes will one day completely replace humanity as the new "master race."
Athas is... different to the standard realm in the Great Wheel. Looking across various sources (most prominently "Defilers & Preservers" and "Earth, Air, Fire & Water" for Dark Sun itself) reveals that Athas is connected to only a small handful of planes; the Gray, the Black, and the Elemental Planes. Further differentiating its cosmology, whilst Athas retains connections to the four standard "True" Elemental Planes (Earth/Air/Water/Fire), it only has four Paraelemental Planes consisting of Magma, Rain, Silt and Sun.
The Gray is essentially the afterlife of Athas; a dreary, endless limbo realm of dismal mists, which serves to blockade Athas from both the Ethereal Plane proper and the Astral Plane. Depending on who you ask, it's either Athas's "Border Ethereal" or an analogue region for the Astral Plane.
The Black is analogous to the Plane of Shadow, and mostly serves as a prison for Rajaat.
It's noted that Athas is unusually close to the Elemental Planes, and this is, in part, why the world is so screwed up.
Athas can actually interact with the Great Wheel, and be reached by Spelljammers, but it's extremely difficult to do so - the whole thing is effectively a sealed zone, as if something trapped the entire pocket of reality inside a locked room.
- The Githyanki are known to have opened a portal to Athas and tried to invade... then they ran home with their tails between their legs and closed up the portal, before leaving behind the proverbial sign saying "Do not open this fucking door!" Athasian Gith are believed to be the degenerate remnants of githyanki stranded here as a result of the failed invasion.
- The Mists of Ravenloft can also reach into Athas and pluck victims into its embrace. There's even an Athasian Domain of Dread called "Kalid-Ma". It says something about life on Athas that being stuck in the Demiplane of Dread is actually perceived by most Athasians as a step up.
- The World Serpent Inn hosts at least one known two-way portal to Athas.
As beloved as it is by the fandom, Dark Sun has... its share of base-breaking lore. Three major things tend to be either loved or hated by fans of the game.
The Halfling Conspiracy
A lot of people are less than impressed with the revelation that halflings were the precursor race and that Dark Sun became such a fucked up world because one psycho wanted to go back to the days when halflings (and technically thri-kreen) were the only extant race.
Beyond the Prism Pentad
As mentioned above, the changes of the Prism Pentad tie-in novels really messed up with the status quo of Dark Sun. Beyond killing off a bunch of Sorcerer-Kings, it also created the Cerulean Storm, an enormous perpetual rain storm wandering randomly across Athas, bringing water back to the planet but at the same time doing so with such violence that it's almost as bad as the original drought.
Mind Lords of the Last Sea
This module, which reveals there is one last sea on Athas, is pretty controversial for various different reasons. Such as the existence of a place where a secretive bunch of psion-lords use telepathy to force people to comply with social standards, the existence of a large body of water on Athas, the fact that it retcons that lizardfolk aren't extinct (but then, ssurans were basically fireproof lizardfolk under a different name all along and nobody batted an eye at them), or the fact that it has actual telepathic dolphins and surfing rules in it.
On the other hand, some people like the idea of doing The Prisoner by way of Mad Max, and the actual content isn't quite as stupid and poorly-written as its reputation suggests, with lots of discussion of how many Athasians would react to seeing the titular Last Sea when enough water to fill a bathtub is wealth beyond measure.
3e Dark Sun
In a surprisingly cool move by Hasbro, fan groups were given official permission to update several orphaned settings to 3rd edition for free (or one not so free in exchange for a check). In Dark Sun's case this spawned Athas dot org and its several PDFs updating the setting.
A separate update was published in Dragon Magazine #319. This one is far more divergent than the fan conversion, setting the timeline forward 300 years to restore the status quo after the Prism Pentad fuckup. This update uses the standard 3rd edition class lineup, making Templars just Clerics of their respective Dragon King instead of their own class and having Paladins actually exist. Since the psioncs book was already needed for psionics, Half-Giant and Thri-Keen, the other races from that book have been thrown in for the hell of it. One unusual mechanical change is how it adapted the higher than average ability score generation Dark Sun used and that several of its races were already printed with Level Adjustment: The conversion decided to give everyone Level Adjustment +1, giving the non-LA races (like Human) extra stuff to bring them up to LA +1.
4e Dark Sun
Surprisingly, when Dark Sun made it into 4th edition, it was welcomed with great warmth and enthusiasm. This might be because WoTC had learned from the mistakes of Forgotten Realms and so whilst there were changes to 4e, none of them were as setting-breaking as the Spellplague, and many actually regarded these changes as being for the better.
What changed? Well...
Cosmology: Athas is now a world where, during the Dawn War, the Primordials won and killed the Gods. The Elemental Chaos replaces the Elemental Planes. The Gray is still around, and is the local name for the Shadowfell, but the Black isn't mentioned. If one makes it through the Gray into the Astral Sea, it's empty; the Gods are dead, their halls are abandoned, and there's nothing but ancient celestial ruins and cosmic battlefields to scavenge through. The Feywild exists, but has been almost completely destroyed by defiling and its remaining pockets are zealously guarded by the Eladrin. The moons of Ral and Guthay are rich, verdant worlds in their own right, according to astrologers, but beyond the rumored existence of unpredictable "moongates" that allow access to them, nothing more is mentioned.
Races: Half-Giants lost their ADHD and are now a reflavoring of Goliaths, mechanically. Dray went from an obscure race hidden in one module to being mentioned in the core, although mechanically they're just reskinned Dragonborn. Eladrin and Tieflings are in the setting now, as the bitter survivors of the nearly-destroyed Feywild and fiend-worshipping cannibal raiders from the depths of the wastelands respectively. A Dragon Magazine article states that there are Genasi on Athas who were originally created to rule the mortal races for the Primordials after they fucked off, but they screwed up so badly they were overthrown and then Rajaat came along. Some races (and horses) previously stated to be extinct are present.
Classes: All Divine classes are officially Not Present Here, although there is a sidebar for being The Last Cleric In The World if you really must. Shamans, Ardents, Bards and Warlords take up the healer's niche. A new pair of themes, the Elemental Cleric and the Primal Guardian, fill the niches of the Elemental Cleric and the Athasian Druid from AD&D. Defiling is no longer a variant Wizard, but a power that any Arcane caster can risk using. Templars went from their own class to being your choice of either a theme or a subclass for the Warlock.
History: The halflings as precursors is no longer explicit fact.
Timeline Reset: The "default setting" in Dark Sun is now just after the Sorcerer-King of Tyr was assassinated by unknown parties. There is NO metaplot, no timeline advancements, nothing; officially, all Dark Sun 4e material is set at this starting point and it's up to the individual DM to decide what, if anything, has happened since Kalak was killed. And there was Much Rejoicing.
Hey, you remember that bit up at the top where Elemental Shamans summon water elementals for people to drink, since there's (supposed to be) no water left on the planet? Well the thing is, assuming everyone's bladders and sweat glands are functioning properly, this by itself should logically be enough to gradually repair Athas.
That said, as bodies of water would gradually start to form and grow more accessible (and these would be bodies of actual water, not urine and sweat, as there's a reason Earth's oceans are still composed of water and not prehistoric dinosaur urine), there'd be less and less reason to keep an elemental-summoning shaman around. "Why should I pay that shaman for a glass when I can walk to the lake for free?" So the rate of repair would get slower and slower as time went on, possibly completely plateauing before the job was finished.
Of course plugging this hole is as simple as positing a route for water to be lost from the environment. Maybe sandtrout are sequestering it underground. Maybe the Primordials are taking some to be dicks. Maybe water from elementals eventually drifts back to the Elemental Chaos.
A tougher plot hole to work out is, how has no one figured out that full body robes are much better protection in the desert than going borderline-naked? Do the locals all have inherited UV protection? Does the sun not shine in the UV spectrum so sunstroke isn’t a thing?