Ioun stone

Ioun stones (), originally called Congenio's pebbles and Ioun's stones, were magical stones that floated around a bearer's head and granted a range of enhancements or powers to a creature.
==Description==
They were small, crystalline stones, coming in a wide range of colors and shapes that determined their powers. Unattended ioun stones tended to hover and drift about by themselves. They were known to glow and occasionally to emit faint, musical sounds, sounding rather like chimes or a harp, in single notes or longer chords.
==Function==
Ioun stones hovered permanently in the air, but otherwise remained motionless.
When one acquired a stone and wished to receive its benefits, they had to first hold it firmly for a brief time in order to attune themselves and imprint their own magnetic aura into its structure, and then release it or toss it in the air. Thereafter, when functioning, the ioun stone orbited the bearer's head at a distance of , or else trailed after the bearer as they walked. Its path was affected by the user's own magnetic field: it generally followed a circular or elliptic pattern but could at times follow a random path, float unmoving in the air, or dance and bob erratically. Occasionally, a stone might drift up to from its owner, then swiftly return. Some users noted that if they examined something closely, then their ioun stones would move toward it.
An ioun stone held stored magical energy. An orbiting stone created a link with its owner, through which it regularly transferred small packets of this energy to them. This magical energy could enhance them in the various ways ioun stones were known for, or bestow more unusual powers. They could only bestow their benefit on an owner when orbiting within the given range. Two stones of the same type would repel each other, but many of different types could be used at once. After 1372 DR, there were also lesser ioun stones that gave the same benefits as full examples of their kind, but only one lesser ioun stone could be used at a time, even if of different types.
The bearer could freely grab and pocket a stone, such as when going to sleep, to keep it safe, but they could no longer receive its benefits. Another person could try to catch or net a hovering stone to steal it or break it. In any case, if shifted more than from its owner, they ceased to function. If the user went to sleep without storing them, the stones hovered motionlessly over them. If the user was injured and lay dying, the orbit of the stones slowed and stayed close to their head. If the user died, the stone slowly drifted off in a random direction before slowly falling to the ground. However, if the user died suddenly or violently, the stone flew off at great speed in a random direction, fast enough to hurt if it impacted someone, or else hitting the ground up to away.
Some stones had only one or a set number of charges, after which they became drained of power and were considered burned out. Rarely, an ioun stone spontaneously burned out on its own (a 1-in-20 chance each year). Either way, a burned-out stone became dull grey and inert, but it still possessed the characteristic floating power. Although they were useless for magical purposes, they retained sufficient resonance for a psionicist to extract a smidgeon of psionic energy—enough to boost their psionic strength or to fuel the lowest of unaugmented powers—before it became completely burned out.
As with other items that could store magical energy, the pale lavender ellipsoid, lavender-and-green ellipsoid, and vibrant-purple prism could store spellfire. In turn, they could also be drained by a spellfire wielder.
Cursed and supercharged versions were known to exist.
==Creation==
Ioun stones could only be created by a veteran spellcaster well versed in the crafting of wondrous magical items.
Only certain types of gemstones could be transformed into an ioun stone through application of the appropriate and generally secret spells. These gems were traditionally known collectively as "the nine secrets": amethyst, chrysoberyl, chrysoprase, greenstone, hematite (though this was rarely known to even powerful wizards), Laeral's tears (most little-known and rarest of the gems), obsidian (the most well known), onyx, and sardonyx. Despite this, others were known to work, like iol (also known as iolite or cordierite, and the most effective of the gems, but not counted as one of the nine secrets). In the time of ancient Netheril, the gems and stones selected for enchantment were actually imperfect or flawed, with the exception of the perfect euhedral stone.
Some ioun stones were apparently created using essences taken from a soul, and bestowed the benefits of these upon their owners. According to legend, the pearly-white ovoid was created from the enslaved soul of a troll, and granted the troll's ability to regenerate wounds. The pale green ioun stone came about when the dying warrior Rigar Trueblood begged his companion, the mage Spectorial, to preserve his skill and fortitude in battle. Although reluctant, Spectorial acceded and extracted these qualities from Rigar's soul, placing them in an ioun stone so that others might benefit from them. The unique Malla's soul stone, which acted as an ioun stone, contained the soul of an innocent young woman, and conferred many different benefits. Similarly, the mantle stone of Vhyridaan was a failed attempt to create a kiira that absorbed its creator, body and soul. Containing the trapped soul of the mage Vhyridaan the Mad, this unique ioun stone was a sentient item that Vhyridaan could steer somewhat to evade attacks.
On the other hand, some ioun stones seem to have merely been created from the blood of creatures with the necessary essences. Legend told that the Trollblood ioun stone, a dark-green sphere, was created from the blood of seven trolls that had each been captured and, over seven nights, used in experiments in magic. The ioun stone that was produced conferred a weaker form of a troll's ability to regenerate wounds, but also gave great skill in slaying trolls in combat.
On the world of Oerth, wizardly charlatans used a spell called false ioun stone to create shallow copies of these wondrous items.
==Other Applications==
Ioun stones did not need to be set orbiting the head; it was possible to mount them in magical items kept close to the body. One possible example was the ioun blade, a +1 dagger with a socket in its hilt or pommel that could hold an ioun stone and bestow its benefit upon the wielder.
Related magic items were the gems of detection. These were miniature ioun stones, highly polished but of weaker material, that could be set into a chair. If one sat in the chair and touched the gem, they could use a specific detection spell, according to the gem, but only while seated in the chair.
There was value and use in burned-out ioun stones; for example, an apothecary in Loudwater in 1479 DR sold them.
==History==
thumb|right|Rimmen of the Scarlet Eye, a magelord with a dusty rose prism.
Congenio Ioun, an early arcanist of the Nether Age of Netheril, created the first ioun stones in the year 397 NY (−3462 DR). At the time, Netherese priests and wizards alike believed that large objects such as shields and suits of armor were simply too big to be enchanted, and (mistakenly) assumed that only small or slender items—pebbles, small stones, pieces of cloth, daggers, and the like—could be enchanted to bear magic. Congenio worked under this assumption and so he worked exclusively with small, semi-polished stones, creating what were later thought to be the first true magical protection devices. This was a previously unheard-of achievement: he was aged only 33 and this was the first magical item he had created, marking him as one of the greatest arcanists of his age.
He initially called them Congenio's pebbles. He adopted the self-imposed limitation of enchanting all stones of the same shape with the same spell, making them more consistent for buyers and eliminating confusion. Congenio's pebbles soon became enormously popular with his fellow arcanists, and were in great demand. Over the next 54 years, the anhedral, echinid, hexagonoid, spindle, pebble, star, and round stones were developed and introduced. Following his model, it was common to enchant small stones or modest gems with basic spells like bless or shield to protect a warrior in battle.
In 451 NY (−3408 DR), at the suggestion of a close friend, Congenio renamed his pebbles to the much more catchy Ioun's stones. Under this name, the cephaloid, cube, cylinder, decipton, dendroid, dodecahedron, ellipsoid, enneid, euhedral, hectoid, helicid, heptid, monoclinoid, nephroid, ovoid, octahedron, orthorhomboid, peg, pentahedron, prism, pyramid, rectangle, septahedron, sexahedron, tile, and tredyhedron stones were created and became widespread in Netheril.
Congenio himself created over thirty of these, including the prism that allowed one to see in the dark and another that granted its holder a temporarily raised level of experience and might.Apart from the prism, it is unknown which pebbles and stones were created by Congenio and which by fellow arcanists, but it is clear that the majority were made by Congenio. It is also clear that Congenio created some stones that are not listed. He was never seen without them orbiting his head. He lived an incredibly long life, almost a thousand years, and some wondered if one of his stones was responsible for his longevity. Congenio finally passed away in 1319 NY (−2540 DR), but for his creations his name lived on for millennia.
After his death, a number of other arcanists continued his work. These researchers made breakthroughs in Congenio's original design, in that they simply ignored his consistent design and placed their own spells on whatever gem they had, no matter its shape. The stones became generally known as simply ioun stones around 1365 NY (c. −2494 DR). From this time on, the triclinid, tubule, decahedron, heptahedron, lozenge, rhomboid, rod, sphere, stelloid, and tetrapton stones were invented, until the fall of Netheril in 3520 NY (−339 DR).
A unique incandescent blue ioun stone surfaced around 1311 DR in Icewind Dale. In a past age, the githzerai craftsman Bashenee had created it for a great githzerai monk, who later fell in battle with githyanki. It circulated among them for many years, until it was given to the mind flayer Oinchack'olp, who treated it as a prized possession. Oinchack'olp was roaming the Underdark beneath Icewind Dale when he lost it, and some driders found it. Oinchack'olp ordered some passing adventurers to retrieve it.
By the 14 century, ioun stones were much desired, yet few people—even those who had them—knew where they had originated. Congenio Ioun himself had been long-forgotten, but his name lived on in his greatest creation. Only some sages of the arcane such as Prismal the Outrageous knew something of Congenio Ioun's story.
Circa 1368 DR, the blood-red sphere, which improved balance, reflexes, and hand–eye coordination, was in great demand among those who used such skills such as rogues, thieves, and their ilk. Similarly, mages and wizards eagerly sought the bronze ovoid, which allowed one to memorize an extra high-level arcane spell, and the golden ovoid, which increased intellect.
==Notable Collections==
Ioun stones were, at all times, quite rare and just as hard to acquire. They were a much-valued treasure, and considered well worth any risk to gather in numbers, owing to their useful powers.
Larloch, the Shadow King, the arch-lich of Warlock's Crypt and a long-surviving arcanist of Netheril, possessed over two dozen ioun stones, which orbited his skull at all times, giving him a wide variety of powers, protections, and enhancements. Some were much more powerful than their regular versions, and he had multiples of some.
In the Year of the Black Flame, 229 DR, in the kingdom of Athalantar, tales spread that a chest full of ioun stones had been discovered in the castle of Athalgard, in the city of Hastarl. They'd likely been hidden by King Uthgrael Aumar (reigned 183–216 DR) years before. The magelords of the kingdom argued over how they should be used—and how they should be shared among themselves. Until agreement was reached, King Belaur Aumar ordered that they be put on display to the public, under heavy guard in an audience chamber, to which wizards were forbidden to approach. The thief Farl had a notion to steal them, but his friend Eladar warned it all could be a trap laid by the magelords.
The Wyvern Crown of Cormyr was inlaid with ten ioun stones on the tips of its spikes. None of the stones could be removed from the Crown without destroying them, not without a wish spell on each stone.
A ring of a dozen ioun stones was occasionally sighted hovering above the River Vesper in the Vast from the 1350s DR on. The stones avoided efforts to grab them, and by 1370 DR, no one with a net, the ability to fly, or a magical means of catching one was lucky enough to spot the ring. A tale told in riverside taverns claimed that anyone who could grab one of the ioun stones could keep it, but was also compelled by a geas to perform some dangerous task, with a different task for each stone.
==Known Ioun Stones==
The following tables list the known ioun stones in each era, together with their benefits, costs, and other details.
In addition to these, it was rumored that Congenio Ioun himself had created another stone that had given him his great longevity; he lived almost a thousand years. He was also recorded as creating another that granted its holder a temporarily raised level of experience and might.
In the time of Netheril, to	In the time of Netheril, to 	In the time of Netheril, to
Congenio's pebbles, to 	Congenio's pebbles, to 	Congenio's pebbles, to
Description 	Benefit 	Cost (gp)
Anhedral 	A blessing to defense 	
Echinid 	A continuous detect magic spell 	
Hexagonoid 	A detect poison spell, humming softly when a poison was detected 	
Spindle 	A brief invisibility to animals on command, 1/day 	
Pebble 	A brief invisibility to undead on command, 1/day 	
Star 	A brief light spell on command, 1/day 	
Round 	A continuous read magic spell 	
Ioun's stones, to 	Ioun's stones, to 	Ioun's stones, to
Description 	Benefit 	Cost (gp)
Cephaloid 	Projected obscure alignment within 20 ft (6 m) 	
Cube 	Increased dexterity and agility 	
Cylinder 	Slight resistance to acid 	
Decipton 	Gem emitted continual light on command 	
Dendroid 	Increased one selected area of physical or mental prowess, as the cube or enneid 	
Dodecahedron 	Increased constitution and fortitude 	
Elipsoid 	Slight resistance to poisonous gases 	
Enneid 	Increased charisma 	
Euhedral 	A perfectly formed, mirror-faced stone, possessing the powers of two other stones 	
Hectoid 	Increased strength 	
Helicid 	Allowed user and 200 lbs (91 kg) of possessions to turn gaseous for an hour 	
Heptid 	Healed the bearer if they lay dying, but the stone crumbled to dust 	
Monoclinoid 	Prevented infravision within 20 ft (6 m) 	
Nephroid 	Slight resistance to magic 	
Ovoid 	Allowed one to walk on water for 1 hour/day 	
Octahedron 	Protected owner with continuous mind blank 	
Orthorhomboid 	Increased intellect 	
Peg 	Granted ten extra arcs, songs, or winds for Netherese arcanists, bards, or priests, respectively	
Pentahedron 	Allowed owner to move freely for 1 hour/day 	
Prism 	Allowed one to see in magical darkness 	
Pyramid 	Regenerated wounds or damage 	
Rectangle 	Slight resistance to poison 	
Septahedron 	Provided the benefit of a strength spell for 1 hour/day 	
Sexahedron 	Allowed user and 200 lbs (91 kg) of possessions to teleport, but the stone crumbled to dust 	
Tile 	Projected a brief antimagic shell, but the stone crumbled to dust 	
Tredyhedron 	Increased wisdom 	
Ioun stones, onward 	Ioun stones, onward 	Ioun stones, onward
Description 	Benefit 	Cost (gp)
Triclinid 	Slight resistance to magical and natural fires 	
Tubule 	Granted infravision 	
Decahedron 	Allowed the user to go without water indefinitely 	
Heptahedron 	Slight resistance to electricity 	
Lozenge 	Slight resistance to charm spells 	
Rhomboid 	Absorbed injury inflicted on owner, but the stone crumbled to dust 	
Rod 	Continuous comprehend languages 	
Sphere 	Slight resistance to petrification effects 	
Stelloid 	Allowed the user to go without food indefinitely 	
Tetraption 	Slight resistance to magical and natural cold 	
Ioun stones around the 8 century DR	Ioun stones around the 8 century DR	Ioun stones around the 8 century DR 	Ioun stones around the 8 century DR
Name 	Description 	Benefit 	Cost (gp)
Mantle stone of Vhyridaan 	 	Stores spells and reflects attacking spells	Unique
Ioun stones around 1281 DR	Ioun stones around 1281 DR	Ioun stones around 1281 DR	Ioun stones around 1281 DR
Name 	Description 	Benefit 	Cost (gp)
Clear ioun stone 	Transparent sphere 	Increased magic resistance	5,000
Deep red ioun stone 	Deep red sphere 	Increased dexterity 	5,000
Scarlet/blue ioun stone 	Red and blue sphere 	Increased intelligence 	5,000
Ioun stones around 1311 DR 	Ioun stones around 1311 DR 	Ioun stones around 1311 DR	Ioun stones around 1311 DR
Name 	Description 	Benefit 	Cost (gp)
Githzerai-made incandescent blue ioun stone	Incandescent blue ioun stone	Increased wisdom 	Unique
Ioun stones after the Time of Troubles (1358 DR)	Ioun stones after the Time of Troubles (1358 DR)	Ioun stones after the Time of Troubles (1358 DR) 	Ioun stones after the Time of Troubles (1358 DR)
Name 	Description 	Benefit 	Cost (gp)
 	Blue-green spindle 	Casts airy water at will 	5,000
 	Brass lozenge 	Heals or gives greater health, up to twenty times 	5,000
 	Bright-silver cylinder 	Allowed user and 200 lbs (91 kg) of possessions to turn ethereal for one hour, up to twenty times 	5,000
 	Bright-white rectangle 	Slight resistance to acid 	5,000
 	Brown rhomboid 	Allowed user and 200 lbs (91 kg) of possessions to turn gaseous for an hour 	5,000
 	Cerulean-blue rhomboid 	Allowed owner to move freely for 1 hour/day 	5,000
Spirit storage 	Clear pink sphere 	Absorbs the soul of the user at the point of death, allowing resurrection via a restoration spell 	5,000
 	Clear prism 	Stores spells 	5,000
 	Clear sphere 	Slight resistance to magic 	5,000
 	Copper rectangle 	A continuous read magic spell 	5,000
 	Dark-green ellipsoid 	Granted clairaudience 	
 	Deep-black sphere 	Allowed one to see in magical darkness 	5,000
 	Deep-purple prism 	Granted infravision 	5,000
 	Deep-red sphere 	Increased strength 	5,000
 	Flickering white snowflake 	Slight resistance to magical and natural cold 	5,000
 	Gold ellipsoid 	Allowed user and 200 lbs (91 kg) of possessions to astral travel for an hour, up to twenty times 	5,000
 	Green sphere 	Slight resistance to gases 	5,000
 	Incandescent blue sphere 	Increased spell ability 	5,000
 	Light-blue prism 	Ability to understand languages spoken 	5,000
 	Maroon star 	User could only be hurt by magic and magical weapons 	5,000
 	Orange cube 	Resistance to mind-affecting spells 	5,000
 	Pale-green ellipsoid 	Absorbed high-level spells, until it burned out and could never be restored 	5,000
 	Pale-lavender spindle 	User could go without food or water 	5,000
 	Pale-yellow lozenge 	Allowed water walk at will 	5,000
 	Pearly white prism 	Repairs damage 	5,000
 	Pink ellipsoid 	Increased constitution 	5,000
 	Pink-and-green ellipsoid 	Absorbed low-level spells, until it burned out and could never be restored 	5,000
 	Puce cube 	Granted ability to read thoughts as ESP at will 	5,000
 	Pulsing red star 	Slight resistance to fire 	5,000
 	Pure-white octahedron 	Increased charisma with members of the same race 	5,000
 	Rainbow ellipsoid 	User may levitate at will 	5,000
 	Rainbow spindle 	Allowed user with 200 lbs (91 kg) of possessions to polymorph spell for one hour, up to twenty times 	5,000
 	Scarlet-and-blue sphere 	Increased intellect 	5,000
 	Silver rod 	Slight resistance to electricity 	5,000
 	Silver sphere 	Prevented user from being attacked from behind 	5,000
 	Silvery mirror cube 	Slight resistance to petrification via sight 	5,000
 	Soft-black rectangle 	Slight resistance to draining of life 	5,000
 	Yellow sphere 	Gem emitted continual light on command 	5,000
 	Blood-red ellipsoid 	Vampiric regeneration 	
 	Deep-purple sphere 	Protection against poison, as a periapt of proof against poison 	
Ioun Eye 	Crystalline eye 	Enables 360° vision at all times, and enables a blind user to see normally 	1,500
Trollblood ioun stone 	Dark-green sphere 	Increased martial prowess against trolls, and may regenerate wounds 	4,000
blood red ioun stone 	Blood-red sphere 	Enhanced balance, reflexes, and hand–eye coordination 	5,000
dusty rose ioun stone 	Dusty-rose ovoid 	Has a calming aspect, but only bestows a basic protection 	5,000
Pale green ioun stone 	Pale-green ovoid 	Combat skill and fortitude 	5,000
pearly white ioun stone 	Pearly-white ovoid 	May regenerate wounds 	5,000
 	Bronze ovoid 	May memorize an extra high-level arcane spell 	
 	Golden ovoid 	Increased intellect 	
 	Bright lavender ovoid 	Protection in battle and resistance to death 	
 	Obsidian ovoid 	Increased constitution and fortitude 	
 	Silver ovoid 	Increased wisdom, as with age and experience 	
Balian's yellow ioun stone 	Yellow 	Temporarily increased charisma, constitution, dexterity, intelligence, strength, or wisdom; randomly chosen, once per day.	5,000
Malla's soul stone 	Star sapphire 	Various benefits 	Unique
Wong Fei's ioun stone 	Ovoid 	Various benefits 	Unique
Purification stone 	Silvery-gray 	Immunity to disease and poison, and may cast neutralize poison once per day 	5,000
Ioun stones after the Year of Wild Magic (1372 DR)	Ioun stones after the Year of Wild Magic (1372 DR)	Ioun stones after the Year of Wild Magic (1372 DR) 	Ioun stones after the Year of Wild Magic (1372 DR)
Name 	Description 	Benefit 	Cost (gp)
 	Clear spindle 	May go without food or water 	4000
 	Dusty-rose prism 	Insight to defense 	5000
 	Deep-red sphere 	Enhanced agility & dexterity 	8000
 	Incandescent-blue sphere 	Enhanced wisdom 	8000
 	Pale-blue rhomboid 	Enhanced strength 	8000
 	Pink rhomboid 	Enhanced constitution 	8000
 	Pink-and-green sphere 	Enhanced charisma 	8000
 	Scarlet-and-blue sphere 	Enhanced intellect 	8000
 	Dark-blue rhomboid 	Greater alertness 	10,000
 	Rainbow 	Provides psionic energy as a cognizance crystal, recharges each day 	16,000
 	Vibrant-purple prism 	Stores spells as a ring of spell storing or psionic powers 	36,000
 	Iridescent spindle 	May go without air 	18,000
 	Pale-lavender ellipsoid 	Absorbs low-level spells or powers as a rod of absorption when readied, until it burns out and turns dull gray	20,000
 	Pearly-white spindle 	May regenerate wounds as a ring of regeneration (for living beings) 	20,000
 	Pale-green prism 	Greater talent in attack, skill, resistance, and physical and mental feats 	30,000
 	Orange prism 	Increasing level of spellcasting 	30,000
 	Lavender-and-green ellipsoid 	Absorbs all but the highest-level spells as a rod of absorption when readied 	40,000
 	Bright silver cylinder 	Ability to turn ethereal as with a cloak of etherealness 	
 	Cerulean blue rhomboid 	Continuous freedom of movement, as the ring 	
 	Dark-green ellipsoid 	Greater fortune in defense 	
 	Dark-orange dodecahedron 	Resistance to spells 	
 	Dark-purple triangle 	Double the number of 3rd-level spells, as a ring of wizardry III 	
 	Dark-purple pyramid 	Double the number of 4th-level spells, as a ring of wizardry IV 	
 	Dark-red cube 	The ability to read minds, as a medallion of thoughts 	
 	Dull-orange rhomboid 	Absorb magic missiles, as a brooch of shielding 	
 	Mottled-gray sphere 	Counters selected spells, as a ring of counterspells 	
 	Pale-white sphere 	Recalls an already-cast spell, as a pearl of power 	
 	Pearlized brown ellipsoid 	A brief haste effect, as boots of speed 	
 	Pearly black spindle 	May regenerate wounds as a ring of regeneration (for undead beings) 	
 	Rich green star 	A slight boost in fortune in survival, skills, and other acts, as a stone of good luck 	
 	Shining black spiral 	May teleport thrice a day, as a helm of teleportation 	
 	Black-and-white ellipsoid 	Protected owner from scrying like the mind blank spell, without the additional benefits of that spell. 	60,000
 	Dull gray 	Provides a smidgeon of psionic energy to a psionicist before completely burned out 	36,000
Ioun Stone of Resistance 	Typically burnt orange 	Provides resistance to harmful effects, comes in various strengths 	2,000–50,000
Mantle stone of Vhyridaan 	 	As a vibrant-purple prism, stores spells and reflects attacking spells 	232,560
Ioun stones around 1479 DR, after the Spellplague	Ioun stones around 1479 DR, after the Spellplague	Ioun stones around 1479 DR, after the Spellplague 	Ioun stones around 1479 DR, after the Spellplague
Name 	Description 	Benefit 	Cost (gp)
Ioun Stone of Adaptation 	Clear crystal 	May go without food or drink indefinitely, and unaffected by extreme temperatures or rain. Can also be used to end an ongoing negative condition.	225,000
Ioun Stone of Perfect Language 	White and pink rhombic prism 	Greater social skills, ability to understand all spoken languages, ability to speak and be heard in all languages, and perfect insight 1/day 	325,000
Ioun Stone of Regeneration 	Red ovoid 	May regenerate wounds or damage when wounded 	625,000
Ioun Stone of Steadfastness 	Pale aquamarine prism 	Immunity to fear when among allies, and cannot be forced to strike an ally 	425,000
Ioun Stone of Sustenance 	Rhombic stone 	May go without food, drink, or air indefinitely, and only need half the normal rest time 	225,000
Ioun Stone of True Sight 	Dark blue rhomboid 	Darkvision, great insight and perceptiveness, and power to see invisible creatures once a day 	1,125,000
Ioun stones around 1490 DR, after the Second Sundering	Ioun stones around 1490 DR, after the Second Sundering	Ioun stones around 1490 DR, after the Second Sundering	Ioun stones around 1490 DR, after the Second Sundering
Name 	Description 	Benefit 	Cost (gp)
Ioun Stone of Absorption 	Pale lavender ellipsoid 	Counters lower level spells up to a limit 	Very Rare
Ioun Stone of Agility 	Deep red sphere 	Increased dexterity 	Very Rare
Ioun Stone of Awareness 	Dark blue rhomboid 	Never surprised 	Rare
Ioun Stone of Fortitude 	Pink rhomboid 	Increased constitution 	Very Rare
Ioun Stone of Greater Absorption 	Marbled lavender-and-green ellipsoid 	Counters higher level spells up to a limit 	Legendary
Ioun Stone of Insight 	Blue sphere 	Increased wisdom 	Very Rare
Ioun Stone of Intellect 	Marbled scarlet-and-blue sphere 	Increased intelligence 	Very Rare
Ioun Stone of Leadership 	Marbled pink-and-green sphere 	Increased charisma 	Very Rare
Ioun Stone of Mastery 	Pale green prism 	Increased proficiency 	Legendary
Ioun Stone of Protection 	Dusty rose prism 	Harder to hit in combat 	Rare
Ioun Stone of Regeneration 	Pearly white spindle 	Hourly health benefit 	Legendary
Ioun Stone of Reserve 	Vibrant purple prism 	Low-level spell storage 	Rare
Ioun Stone of Strength 	Pale blue rhomboid 	Increased strength 	Very Rare
Ioun Stone of Sustenance 	Clear spindle 	No need for food or drink 	Rare
==Appendix==
===See Also===
* Gem of detection
* Golden orb of Siluvanede
* Warfu stones
===Notes===
===Appearances===
===Gallery===
Yellow ioun stone.jpg|A yellow ioun stone.
Ioun stone of mastery.png|An ioun stone of mastery from Chult.
Ioun_absor_WoW.png|An ioun stone of absorption from Waterdeep.
Awareness ioun stone WoW.png|An ioun stone of awareness from Waterdeep.
Ioun stone protect.jpg|An Ioun stone of protection from Waterdeep.
Red Dragon Ioun Stone.png|A red dragon ioun stone.
Black Dragon Ioun Stone.png|Acidic aura black dragon ioun stone.
Ioun Stone of Radiance.png|An ioun stone of radiance simmering with Feywild glow.
Ioun Stone of Might.png|An ioun stone of might.
Ioun Stone of Allure.png|A floating ioun stone of allure.
Icosahedron Ioun Stone.png|A twenty-sided icosahedron ioun stone.
Black ice ioun stone.png|Black ice ioun stone.
===Background===
The ioun stone has its basis in the IOUN stone (written all in capitals) appearing in the short story "Morreion" by Jack Vance, whose Dying Earth series was very influential on early Dungeons & Dragons. "Morreion" was first published in the Flashing Swords! #1 anthology in 1973. Here, IOUN stones are valuable items that nullify magic and are extracted at great risk from the cores of dead stars. With Vance's permission, the ioun stone was first developed for D&D in The Strategic Review #4 (1975), with the clear prism, deep-red sphere, incandescent blue sphere, pale green ellipsoid, pale lavender spindle, pearly white prism, pink ellipsoid, pink-and-green ellipsoid, and scarlet-and-blue sphere being the first to appear.
The article "Bazaar of the Bizarre: Ioun Stones" in Dragon #174 (1991) begins by describing Vance's original IOUN stones and presents two possible origins for the ioun stones in D&D. The main one is that ioun stones grow naturally but rarely on the Quasi-Elemental Plane of Minerals, at the intersection of the Elemental Plane of Earth with the Positive Energy Plane, and the article details the hazards in procuring them. The other idea is that powerful human wizards from another Prime Material Plane simply manufacture ioun stones, but describes this as straightforward, uninteresting, and lacking adventure.
Nevertheless, Encyclopedia Magica Volume II (1995) does just that, stating that the powerful human wizard Congenio Ioun invented them. Netheril: Empire of Magic (1996) follows suit, placing this origin in the Forgotten Realms, telling that Congenio Ioun was a Netherese wizard and that subsequent wizards manufactured more, as recounted in this article. Since this is Forgotten Realms material, this is the version adopted for this wiki.
D&D would once again forget and recreate the origin of the ioun stone when 4 edition introduced a goddess of knowledge and prophecy called Ioun, inspired by the ioun stone. Open Grave presents a cursed artifact called the Jet Black Ioun Stone, and says that the goddess Ioun created ioun stones (including the Jet Black) to spread knowledge in all forms. 
The drifting of the origin story continued in 5 edition with the eponymous creator being called a god of knowledge and prophecy, rather than a goddess. The stones were described as having a rigid correlation between the benefit they bestowed and the shape and color of the item. They were considered wondrous items valued by rarity and classified as Rare, Very Rare, or Legendary. Yet, in 4 edition's Mordenkainen's Magnificent Emporium (p.69), the stones were the creation of "the god" of knowledge prophecy, either. But it also mentions priest of Ioun, who debate "their deity’s motives in creating the stones", attributing it clearly to the goddess.
The German translation of 5 edition Dungeon Master's Guide disconnected it even further from it's origin, by translating them into "Ionensteine". By doing so, they where named after an atom or molecule with a net electrical charge (ions) and not an individual or even god named Ioun. Further, the text refers to the (now clearly) male god Ion, not Ioun, who made them, despite the fact that Ioun can be found correctly gendered and translated in the chapter describing the Dawn War sample pantheon. In the German 5.1 SRD, they corrected that. Now it is correctly a female goddess with the name Ioun. Nonetheless, the stones itself are still called "Ionensteine".
Meanwhile, Kara-Tur: The Eastern Realms (1988) introduced warfu stones with similar function. These are presumably intended to be an eastern version of the ioun stones of regular D&D, but a connection between the two is unknown.
===References===
Category:Ioun stones
Category:Magic items
Category:Items from Netheril
Category:Items from Faerûn
Category:Items from Toril
Category:Items