Ethshar

Ethshar is a fantasy setting created by Lawrence Watt Evans.

It's loosely based on the Roman Republic. Currently, the most influential country of the world is the Hegemony of Three Ethshars, which defeated the evil, magic wielding Empire of the North, while the former Ethshar (Old Ethshar) split into hundreds of tiny kingdoms. There's trade, war and pirates...

But above all there are magic users. Ethshar is home of dozens of magic specialists and various kinds of magicians - there's six most powerful ones, and dozens of lesser ones like necromancy or alchemy.

Wizardry - Wizardry taps into essential Chaos of the World, and therefore is thought to be the most powerful kind of magic. A skilled wizard can, if he knows a specific spell, turn frogs into princesses, create illusions, enchant swords, create castles in alternate dimensions or achieve immortality. Most of their spells use a magical dagger called athame, as well as material components like blood of virgin or dragon's tongues.

Sorcery - Sorcery uses the Order from outside the world and is based on the creating enchanted objects that cast spells. They manufacture many powerful devices that can sometimes be used even by the mundanes. Some resemble high-tech devices, others are simply magical.

Warlockry - Warlockry is essentially sufficiently advanced telekinesis, extending to manipulating small objects, or even on the molecular level (electrokinesis, pyrokinesis). Warlocks derive their power from a mysterious Source, but when they become powerful enough, it summons them, never to be seen again.

Witchcraft - Witchcraft is psionics - including mind reading, telekinesis or pyrokinesis - which doubles with warlockry. The power is derived from witch's own strength; doing something by witchcraft is exactly as tiring as doing the same task by mundane means. Consequently witchcraft lacks raw power. On the other hand, witches can use their power in more subtle and efficient ways since they have better extra-sensory perception. Furthermore, witchcraft is quite versatile - witches can even use some basic spells! Unusually, witchcraft isn't gender-specific; both male and female practitioners exist and both are called witches.

Theurgy - theurgists can use prayers to ask gods specific favors. Actual faith is not required and prayers resemble spells. Most theurgists are priests, but the gods aren't really interested in worship.

Demonology - summoning demons and forcing them to do your dirty jobs. Technically it's not illegal (except in some of the Small Kingdoms) nor evil, but it isn't nice. Most demons require souls or blood sacrifice - a few require killing a victim.

Novels set in Ethshar

 * The Misenchanted Sword
 * With a Single Spell
 * The Unwilling Warlord
 * The Blood of a Dragon
 * Taking Flight
 * The Spell of the Black Dagger
 * Night of Madness
 * Ithanalin's Restoration
 * The Spriggan Mirror
 * The Vondish Ambassador
 * The Final Calling

Ethshar novels with their own trope pages include:

 * The Misenchanted Sword

The other novels in this series provide examples of:

 * Addictive Magic: The more a warlock uses his magic, the easier and more pleasurable it gets. But the power's drawn from an external source, and a warlock who uses too much ends up being irresistibly summoned to that source.
 * Anti Magic: There exists a spell that permanently cancels wizard's magic in a large area. Forever. Since the majority of the world operates by magic, the spell has been cast exactly thrice in the history of the world: once on discovery, once as a Deadly Prank against a wizard in a flying castle, and once to negate a universal solvent that was likely to destroy the entire world if unchecked. (Note, however, that it only applies to wizardry; the other half-dozen or so forms of magic are fundamentally different, though less powerful, and so are unaffected.)
 * Beat Still My Heart: Wizards can remove their heart from their body in order to protect the heart from harm. (We don't see the ritual or the removed heart, so whether the heart remains beating or not is a matter of speculation.) This magic is used as a protection against warlocks, who usually kill by telekinetically inducing a heart attack.
 * Blood Magic: Different types of blood are used in many wizard spells. One example is the dragon blood, which is used in some powerful spells and is pretty expensive. Some spells need even more exotic kinds of blood, such as, for example, blood of a gelded dragon. Unusual in that there's no moral stigma associated with this, and there (usually) no Human Sacrifice involved: if a wizard needs blood of a virgin, for example, he just pays a virgin to donate the blood.
 * Deal With the Devil: Practically entire modus operandi of Demonology. The demonologists summon demons to perform needed tasks and pay them with, for example, animal sacrifices. Due to the treacherous nature of demons demonology is a dangerous business: it is stated that sometimes demonologists just disappear...
 * The Empath: One of the effects of witches' magic.
 * Engagement Challenge: Played with in With a Single Spell where the erstwhile dragon-slayers were promised a bag of gold and a princess for defeating the dragon. Upon returning successfully, one of the heroes tries to refuse the princess and take the gold - only to find that it's a package deal. There are too many princesses and the gold is her dowry.
 * Expospeak Gag: Wizards can get answers to yes-or-no questions by using the Spell of the Eighth Sphere, which makes runes appear in a black crystal globe. In other words, a Magic 8 Ball.
 * Eye of Newt: Wizardry uses ingredients like this -- a raindrop caught in midair, for example, or the blood of an unborn child. There's even an expert -- a man named Gresh -- who looks for such things and supplies them to wizards for a living.
 * Flat World: The entire world is said to be the end-cap of a cylinder.
 * From Nobody to Nightmare: Many warlocks went from zero to powerful magicians during single night, aptly named the Night of Madness.
 * Hooker With a Heart of Gold: Rudhira the warlock, Fiery Redhead and former streetwalker.
 * Immortal Immaturity: Eternal youth spells freeze someone at that point in their maturity, and immortal wizards who revert themselves back to youth note that a younger body makes them act differently (especially as regards the libido). One immortal who's been 15 for 200 years is eventually dumped by her 16-year-old beau as being too young (emotionally speaking) for him.
 * Magic a Is Magic A: The author is very good at following established magical rules.
 * Magical Incantation: Used pretty much in all wizard spells, and also in some witch spells.
 * The Magic Goes Away:
 * Mega Manning: The main ability of the titular black dagger from The Spell of the Black Dagger. The wielder of the dagger gets some abilities of whoever or whatever is killed by the dagger: good hearing and low-light vision from a cat, boost of strength from a bull or a strong man, etc. The dagger can even steal magical ability - but not corresponding knowledge, just raw magical talent.
 * Mundane Utility: All over the place. After all, if a wizard can make some money magically cleaning sewers or repairing someone's precious vase, why not?
 * One Steve Limit: Somewhat averted.
 * The name Kelder is very common in Ethshar - almost to the point of being a Running Gag. Practically every novel has some character named Kelder (although so far only one of these Kelders was a protagonist).
 * Sarai is almost as common a girl's name, again appearing in most stories. Irith is also said to be a very common name - "Kelder and Irith" or "Uncle Kelder and Aunt Sarai" are used as generic expressions for ordinary folk.
 * Also thoroughly averted with a city name. The Hegemony has three capitals, and all three are called Ethshar: Ethshar of the Spices (where most of the novels' events take place), Ethshar of the Rocks, and Ethshar of the Sands. And that's not all: there was earlier a kingdom called The Holy Kingdom of Ethshar, or Ethshar for short. (Now it's referred to as Old Ethshar.) Later this kingdom split up into many small kingdoms, many of which claim to be the only rightful heir of Old Ethshar. One of these small kingdoms is called Ethshar of the Plains.
 * Our Demons Are Different: In Taking Flight a demonologist, defending a caravan from robbers, summons a horde of smallish bloodthirsty creatures. Word of God states that he summoned the demon called Ansu of the Many Bodies. Yes, the whole horde was one demon.
 * Ritual Magic: Almost all systems of magic are like this to some extent (the big exception being warlockry). More specifically:
 * Wizardry: all the spells use specific incantations, gestures, and ingredients.
 * Witchcraft: somewhat similar to psionics, but some spells do need specific rituals.
 * Theurgy: uses prayers to ask favors from gods. Prayers must be specific to attract the god's attention (and even with a right prayer, god might not hear theurgist's timbre of voice!).
 * Demonology: uses invocations to summon demons.
 * Sorcery: not exactly ritualistic, but uses magical devices for casting spells.
 * Ritual Song and Ritual Dance: Exactly What It Says On the Tin.
 * Shapeshifting Squick: Unusually, the shapeshifter is the one being squicked. In Taking Flight, a man is enchanted to love and desire Irith the Flier, who is a shapeshifter with seven different shapes. It turns out that no matter the Irith's shape, the man still lusts after her, even when she assumes a shape of a horse. (By the way, one of the seven shapes is a housecat, so yeah, a cat is fine too.) Irith is seriously squicked by that.
 * Shout Out: The spell Felshen's First Hypnotic is presumably named in tribute to Felojun's Second Hypnotic Spell from Jack Vance's Dying Earth series. Also, wizard Fendel is a homage to Archnecromancer Phandaal from the same series (Word of God on the subject here).
 * Sorcerous Overlord: Usually averted, thanks to Wizards' Guild. The Guild's rules expressly forbid any magician, wizard or not, to occupy any ruling position at all (the only exception are those positions that explicitly require magic, like that of a court magician). Punishment for breaking this rule is death.
 * Summon Magic: Demonology. Also, some wizard spells can summon otherwordly creatures, too.
 * Taken for Granite: There are at least two spells for that. Bazil’s Irreversible Petrifaction turns someone to stone permanently, while Fendel’s Superior Petrifaction can be reversed with the right spells (that's why it's considered Superior). Both spells can be used in magical combat, but the reversible spell has some other, more exotic uses.
 * Tabletop Game: There isn't an official one, but Word of God states that many varieties of Ethshar magic, with their rules and limitations, were invented by Lawrence Watt Evans for a homebrew Tabletop Game. (And the idea of the novel With a Single Spell came when one of the players asked the author: "What is the minimum number of spells for a newly-generated wizard?" The answer was "One".)
 * Un Equal Rites: While there're half a dozen major varieties of magic in Ethshar, usually their rivalry is quite mild: higher-ups spy after another guilds, guilds compete a bit... and that is pretty much it. However, when a new and quite powerful variety of magic with previously-unknown limitations - the warlockry - turns up, tensions immediately run very high. Some wizard hotheads even consider just killing all the warlocks as the best solution.
 * Vancian Magic: Wizardry can be like this. In Taking Flight, two fire-and-forget wizardry systems are introduced, both with severe drawbacks. The first one lets wizard prepare any one (but only one) spell in advance, to be used once at his convenience, with practically zero casting time. Can be useful, as some spells need days to cast. The drawback is, until the spell is used, the wizard cannot do any other wizardry. The second system is a plot point:
 * The Wall Around the World: Rather, the yellow fog/gas around the world.
 * Wizards Live Longer: There're spells for that, up to and including immortality (Type II) and eternal youth.