Dark Sun for the new DM

So you’re a newbie DM, and you’re trying to decide whether or not you are going to run a little bit of Dark Sun for your group.  Here are a few things you’ll need to keep in mind if you do, as the standard fantasy fare won’t really apply to the world of Athas.  And what’s the point of playing in Dark Sun if you aren’t going to give it the feel of the setting?  All this is touched on and explained in the book, I am merely highlighting how important it is to follow this in order to give your game the authentic Dark Sun flavor.

• Athas is a desert.  Now would be a good a time as any and take a refresher course on using the Environmental Dangers rules on page 159 of your DMG.  Endurance checks, effects of thirst, and rules on weather should be used to help capture the feel of the world, and reinforce to your players that this is a brutal setting.  The book also introduces a mechanic called “Survival Days” which is a shorthand way to track and manage supplies for treks out in the desert.
• Keep in mind the scarcity of metal in the world.  It would really be a rare occurrence for a PC to have metal weapons.  Instead, weapons are made of items such as bones, or wood, and have a chance to break upon use via the Weapon Breakage rule.  I experienced this rule at Gencon, and it was pretty cool.  My weapon broke as I stuck it in some guy’s gut
• There are no gods, so divine characters are not really part of the world.  You can make them be if you can come up with a reasonable explanation, but my suggestion would be to leave them out and keep with the feel and flavor of the world.
• Races have been turned on their heads.  There are no rivers, so for example Halflings aren’t water gypsies, but rather an ancient race of nature lovers who have no problem eating other people in order to survive.  And elves?  They are desert nomads who live off trading and peddling their wares.  Keep in mind and read the races material in the book, so your players aren’t taken by surprise when a Halfling tries to eat a PC.
• Arcane Magic defiles the land.  When an arcane powered PC uses his magic, he withers plants around him into ash, he sucks the life from the animals and people around him, and renders the land under his feet completely unarable.  All this is explained in the book, and is one of the most iconic things about Athas.  (EDIT:  It was pointed out by a commenter below that a PC can choose to NOT defile, and he’s right.  It’s called Preserving, so you Arcane kids can choose your classes and not worry too much about it.  You can defile if you want, it is nasty.)
• Monster selection is also important to give it the flavor of Dark Sun.  Stick to reptiles and bugs, for example, along with creatures from the Dark Sun Creature Collection.  Lizard folks and elementals are good too.
• Psionics, psionics, psionics.  Psionics affect all living creatures on Athas, so create neat variations of monsters with some that use mind powers and that sort of thing.  Telepathy and telekinetic powers are not all that foreign to folks in Athas, so use them liberally in your encounters.
• Arena fights are a big staple of the setting.  So is slavery.  Slaves?  Arenas?  Bloodbaths. Always fun for a DM.

So there you go, a quick primer on what an Athas game should look like, in case you are wondering on whether or not you should pick up the book.  If you want to try something other than the heavy fantasy of the Forgotten Realms, or the pulp in Eberron, this would be a good option.  It throws so many standard D&D tropes out the window that it makes for a fresh take on the game, and that alone makes it worthy in my book.