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An ioun stone, also capitalized Ioun stone, is a small, magical crystal which orbits the bearer's head, conferring magical powers. A wide variety of different shapes and colors of ioun stone exist, each granting a different magical property. Ioun stones are rare, with some exceptional stones being unique.

"Ioun" is pronounced "eye-yoon".[1]

Appearance and function

When tossed into the air, an ioun stone begins to orbit the bearer's head at a distance of between one and three feet. It confers its magical ability to the bearer until it is removed from its orbit, usually either by the bearer or an opponent attempting to steal the item.[2]

Ioun stones have been known to become attuned to the bearer over time, and react to their mood. Otiluke, the mage of Greyhawk, possesses a pale green prism ioun stone which moves visibly more quickly when he is angry.[3] This ioun stone was later stolen by Rary the Traitor.[4]

Ioun stones are occasionally known to burn out after a long period of use. Rarely, an ioun stone exists which is doubly as powerful as normal, but such stones are even more unstable, with around a 20% chance per year of burning out. Unfinished ioun stones pose a risk of inflicting a debility on the bearer, not unlike a cursed item, whereupon they crumble into dust.[5]

Adventurers are known to cast light spells such as continual flame on their ioun stones to serve as a light source.[6] Clever adventurers and creatures are known to make their ioun stones invisible to prevent them from being stolen.[7]

Ioun stones are thought to improve divination results with Mald Ulad's divining board, a form of ouija board.[8] Ioun stones have a tendency to gravitate toward a havoc orb.[9]

Creation

Nine types of gemstones, known as the "nine secrets", can be used in the creation of ioun stones. These are amethyst, chrysoberyl, chrysoprase, greenstone, hematite, Laeral's tears, obsidian, onyx, and sardonyx. A tenth type, iol, is especially good, with secret spells.[10]

The svirfneblin, or deep gnomes of Faerûn, are particularly adept at crafting magic items from gemstones, including ioun stones.[11]

History

Origin

The origins and history of the ioun stone are varied. It is possible that the ioun stone was invented or discovered independently on different worlds and at different times.

Congenio Ioun

According to the sage Prismal the Outrageous of Faerûn, the ioun stone was first created by Congenio Ioun, a wizard and magic item creator thought to lived over three thousand years ago, with later calculations placing it in the year -3495 DR. At this time, the field of magical artifice was in its infancy, and it was believed that the magical enchantment of large items was impossible. Small gemstones were instead enchanted with low-level protective spells and made to orbit their bearer.[12][13][14]

At the age of 33, Congenio created the first ioun stone, naming his invention Congenio's pebbles. Around 54 years later, at the behest of a close friend, Congenio renamed his invention to Ioun's stones, from which the modern name ioun stone derives. He created more than 30 different stones during his lifetime, living to the age of 955 before finally passing away in the outer planes. In the current era, this would make the ioun stone almost 5,000 years old by the Dalereckoning calendar.[13][15][14]

Divine creation theory

Ancient legends of the Nentir Vale tell another story: that the god Ioun, deity of knowledge prophecy, created these rare stones and gifted them great heroes long ago. The clergy consider the bearer of such an item to be destined for important things. So widely held is this belief that superstitous adventurers avoid using multiple ioun stones for fear of being swept up in some dread prophecy.[16]

Several stones created by this deity draw from seven ancient sages known as the Pillars of Ioun, whose work Ioun chose to honor by establishing great monuments and distilling their legendary traits into the energy which the ioun stones are imbued with. For example, the ioun stone of regeneration was created to honor the eternally unfortunate Garaji Tourmarii, in honor of his ability to pick himself back up whenever he failed.[17]

Natural production

Ioun stones are known to occur naturally in the quasi-plane of mineral, a narrow quasi-elemental plane which occurs at the border of the plane of earth and positive energy plane.[5]

The development of an ioun stone begins when high-quality gemstones within the plane of earth are subjected to high pressure. The resulting proto-geode contains a pseudocrystal core wrapped in an outer layer which is semi-permeable to energy. The nodule is gradually pushed toward the plane of mineral, absorbing positive energy at high concentration. The stones replace up to half of their mass with pure energy, which combined with a developed field of pseudomagnetic repulsion cause the resulting stone to naturally float.

The resulting nodules are pushed toward the border of the positive energy plane, where those which survive the harsh energy are purified into crystal geodes containing ioun stones, which are eventually deposited in the plane of mineral. The entire process takes years, and in some cases centuries.[5]

Spacefaring origin

The elmarin, a space-dwelling creature of living fire, occasionally leave behind an ioun stone upon death.[18] Spacefaring gnomes are known to hunt elmarin for the ioun stones, and it is speculated that the mercane harvest ioun stones from these creatures.[5]

Development

In order to avoid confusion, Congenio Ioun had established that all stones enchanted with a given property must have the same shape. Many later spellcasters ignored Congenio's standards.[15]

Recent history

Many powerful spellcasters of Faerûn are known for owning large numbers of ioun stones. These include Count Gamalon Idogyr of Tethyr (nicknamed "Gem-head" for his collection), the lich Larloch, and Golkont the Hawk-Mage.[19][13][20]

List of ioun stones

  • Amber sphere: "of Divine Knowledge"; Acts as holy symbol, grants insight into an opponent, grants bonus to Insight, Religion and Intelligence checks[21]
  • Anhedral: +1 to AC, as bless spell[15]
  • Balian's yellow: +1 to a random ability score each day[12]
  • Black and white ellipsoid: Provides mind blank effect against scrying[22]
  • Black pyritohedron: Energy drain from creature or magic item; unique ioun stone[23]
  • Black star: Absorbs an amount of electrical damage[24]
  • Blood red ellipsoid: Grants vampiric regeneration.[25]
  • Blood red orthorhomboid: Transmutes 10ft of minerals into energy; unique ioun stone[23]
  • Blue green spindle: Bestows airy water in a 10' radius sphere at will[5][12]
  • Brass lozenge: Gain 2d4+2 HP once per day on command, 2d10 charges[5][12]
  • Brassy stone: "Natural Knowledge"; Rare stone which grants Nature proficiency[26]
  • Bright silver cylinder: User and 200lbs. of possessions can go ethereal for one hour, 2d10 charges,[5][12] as cloak of etherealness, double duration[27]
  • Bright white rectangle: +1 to saves vs acid[5][12]
  • Brilliant green bipyramidal: Infuses target with energy, dealing damage and heating metal; unique ioun stone[23]
  • Brown rhomboid: User and 200lbs. of possessions can assume gaseous form for one hour, 2d10 charges[5][12]
  • Burnt orange: "of Resistance"; Improves saving throws; available in varying degrees of efficacy, and sometimes varies in color.[28][29]
  • Cephaloid: Obscure alignment within 20 feet[15]
  • Cerulean blue rhomboid: Bestows free action on user, as per the magical ring,[5][12] as cloak of etherealness[27]
  • Clear crystal: "of Adaption"; Sustains creature without food or water, resist environmental temperatures, stop ongoing damage[30]
  • Clear interconnected spheres: User becomes insubstantial; unique ioun stone[23]
  • Clear pink sphere: "Spirit storage"; if user is killed in combat, his spirit is transferred to the ioun stone and can be restored with a restoration spell[5][12]
  • Clear prism: Store 2d6 spell levels[12]
  • Clear sphere: Grants 5% magic resistance[5][12]
  • Clear spindle: "Sustenance"; a rare stone which sustains the bearer without food or water[31][2]
  • Clear teardrop: Use detect undead at will[32]
  • Copper rectangle: Allows user to read magic at will[5][12]
  • Cube: +1 to Dexterity[15]
  • Cylinder: +1 to saving throws vs acid[15]
  • Dark blue ellipsoid: Absorbs an amount of damage from magic missile before burning out[24]
  • Dark blue rhomboid: "Awareness"; a rare stone granting Alertness[31][2]
  • Dark blue rhomboid: "of True Sight"; darkvision, +6 to Perception and Insight, 1/day see invisible[33]
  • Dark green ellipsoid: +5 luck bonus to AC[27]
  • Dark green ellipsoid: Grants clairaudience[34]
  • Dark orange dodecahedron: Spell resistance 21[27]
  • Dark purple pyramid: as ring of wizardry IV[27]
  • Dark purple triangle: as ring of wizardry III[27]
  • Dark red cube: as medallion of thoughts[27]
  • Decahedron: Sustain user without water[15]
  • Decipton: Shed continual light on command[15]
  • Deep black sphere: See in magical darkness, 30' range[5][12]
  • Deep purple prism: Grants 60' infravision or doubles existing infravision range[5][12]
  • Deep purple sphere: Works as a periapt of proof against poison.[25]
  • Deep red sphere: "Agility", a very rare stone granting a +2 bonus to Dexterity[31][2][16]
  • Deep red sphere: "Add +1 to Strength[12]
  • Dendroid: Adds one level of ability, not cumulative[15]
  • Dodecahedron: +1 to Constitution[15]
  • Dull gray: Provides psionic 1 power point. then disintegrates[35]
  • Dull orange rhomboid: as brooch of shielding[27]
  • Dusty rose prism: "Protection"; a rare stone granting a +1 insight bonus to armor class[31][2]
  • Dusty rose prism, Larloch's: +5 deflection bonus to AC[27]
  • Echinid: User can detect magic[15]
  • Ellipsoid: +1 to saving throws vs poison gas[15]
  • Enneid: +1 to Charisma[15]
  • Euhedral: Has the power of two ioun stones[15]
  • Faceted sphere: "Supreme Intellect"; Grants a bonus to Intelligence checks[26]
  • Flickering white snowflake: +1 to saves vs cold[5][12]
  • Frosty white octahedron: Contains 1-4 wishes; unique ioun stone[23]
  • Gold ellipsoid: User and 200lbs. of possessions can go astral for one hour, 2d10 charges[5][12]
  • Golden gem: "Religious Knowledge"; a rare stone which grants Religion proficiency[26]
  • Green sphere: +1 to saving throws vs gas attacks[5][12]
  • Green and blue sphere: "Vitality"; +1 to death saving throws[36]
  • Hectoid: +1 to Strength[15]
  • Helicid: User can turn gaseous for one hour[15]
  • Heptahedron: +1 to saving throws vs electricity[15]
  • Heptid: Brings dying creature back to one hit point; stone turns to dust when used[15]
  • Hexagonoid: Hums softly when poison is within 20 feet[15]
  • Incandescent blue sphere: +1 level to spell ability[12]
  • Incandescent blue sphere: "Insight"; a very rare stone granting +2 to Wisdom[31][2] Also known as the iridescent blue sphere.[16]
  • Incandescent blue sphere, Larloch's: +6 bonus to Wisdom[27]
  • Indigo blue trapezohedron: Emits fossilization pulse affecting living beings within 30 feet; unique ioun stone[23]
  • Ioun Eye: Grants 360 degree vision[37]
  • Ioun's Flame: Bonus to Will and knowledge checks, shed light[21]
  • Iridescent spindle: "of Sustenence"; Sustains creature without air[31][16]
  • Jet black: Low-light vision, light sources reduced by half, improve critical range on one target, use stone as spying device, can't knock opponents unconscious[38]
  • Lavender and green ellipsoid: "Greater Absorption"; a marbled-pattern ioun stone of legendary rarity. Absorbs spells of 8th level or lower[31][2]
  • Light blue prism: User can understand all spoken languages[5][12]
  • Lozenge: +1 to saving throws vs charm spells[15]
  • Maroon star: User can only be harmed by magical weapons and spells[5][12]
  • Monoclinoid: Disables infravision within 20 feet[15]
  • Mottled gray sphere: as ring of counterspells[27]
  • Nephroid: Grants 5% magic resistance[15]
  • Octahedron: Protects owner with continual mind blank spell[15]
  • Orange cube: Grants resistance to mind-affecting spells as if user had a Wisdom of 20[5][12]
  • Orange prism: +1 caster level[31]
  • Orthorhomboid: +1 to Intelligence[15]
  • Ovoid: Allows water walking for one hour per day[15]
  • Pale aquamarine prism: "of Steadfastness"; fear immunity[39]
  • Pale blue rhomboid: Called "Strength" or "Ioun Stone of Might"; a very rare stone granting a +2 bonus to Strength[31][2][16]
  • Pale green lozenge: Bestows nondetection[24]
  • Pale green prism: "Mastery"; an ioun stone of legendary rarity granting +1 to most rolls[31][2] Alternately, increases a character's level by one[3]
  • Pale green prism, Larloch's: +5 competence bonus on attack rolls, saves and checks[27]
  • Pale lavender ellipsoid: "Absorption"; a very rare stone which absorbs spells of 4th level of lower[31]
  • Pale white sphere: Recall three 9th-level spells, as pearl of power[27]
  • Pearlized brown ellipsoid: as boots of speed, free action to activate[27]
  • Pearly black spindle: Undead regenerate 1hp/hour[27]
  • Pearly white prism: Repairs 1 point of damage per turn[12]
  • Pearly white spindle: "Regeneration"; a stone of legendary rarity allowing the bearer to regenerate injury each hour[31][2]
  • Pebble: Use invisibility to undead once per day[15]
  • Peg: Provides a bonus ot 10 arcs, wings or songs to spellcaster[15]
  • Pentahedron: Free action once per day for one hour[15]
  • Pink and green ellipsoid: Absorb spells of up to 4th level[12]
  • Pink and green sphere: Called "Leadership" or the Ioun Stone of Allure; a very rare marbled ioun stone granting +2 to Charisma[31][2][16]
  • Pink ellipsoid: Adds +1 to Constitution[12]
  • Pink rhomboid: Called "Fortitude" or the "Ioun Stone of Vigor"; a very rare stone granting a +2 bonus to Constitution[31][2][16]
  • Prism: User can see in magical darkness[15]
  • Puce cube: Bestows ESP at will; user can scan surface thoughts of one person per round within range of 30'[5][12]
  • Pulsing red star: +1 to saves vs fire[5][12]
  • Pure white octahedron: +1 bonus to Charisma vs beings of the same race[5][12]
  • Pyramid: Regenerate one hit point every four hours[15]
  • Rainbow: Provide 5 psionic power points[35]
  • Rainbow ellipsoid: User can levitate at will[5][12]
  • Rainbow spindle: User and 200lbs. of possessions can polymorph self for one hour, 2d10 charges[5][12]
  • Rectangle: +1 to saving throws vs poison[15]
  • Red: Grants water breathing[40]
  • Red crystal: "Language Kmowledge"; A rare stone which grants knowledge of one language[26]
  • Red ellipsoid: "of Regeneration"; regeneration 10 while bloodied 1/day[39]
  • Red sphere: Bestows protection from fire[24]
  • Rhomboid: Absorb 10 points of damage; turns to dust when used[15]
  • Rhomboid: "of Sustenance"; require no food, water or air, and require half normal rest[39]
  • Rich green star: as +5 stone of good luck[27]
  • Rod: User can comprehend language as the spell[15]
  • Round: Continual Read Magic[15]
  • Scarlet and blue sphere: "Intellect"; a very rare marbled pattern stone granting +2 to Intelligence[31][12][2][16]
  • Scarlet and blue sphere, Larloch's: +6 bonus to Intelligence[27]
  • Septahedron: Strength spell once per day for one hour[15]
  • Sexahedron: User can teleport; stone turns to dust when used[15]
  • Shining black spiral: as helm of teleportation[27]
  • Silver rod: +1 to saves vs electricity[5][12]
  • Silver sphere: Negates rear-attack bonuses[5][12]
  • Silvery gem: "Self-Preservation": A rare stone granting a bonus to Intelligence saving throws.[26]
  • Silvery mirror cube: +1 bonus to saves vs petrification gaze attacks[5][12]
  • Singing ioun stone: disguised as any other ioun stone, cursed to fill user's mind with music and disrupt concentration[41]
  • Soft black rectangle: Protection against level-draining attacks, 2d10 charges[5][12]
  • Sphere: +1 to saving throws vs petrification[15]
  • Spindle: Use invisibility to animals once per day[15]
  • Star: Cast daylight[15][42]
  • Stelloid: Sustain user without food[15]
  • Steely sphere: "Historical Knowledge"; a rare stone granting History proficiency[26]
  • Tear of Ioun: A unique divine artifact said to be the most powerful ioun stone in existence[43]
  • Tetrapton: +1 to saving throws vs cold[15]
  • Tigereyes: Polymorphs user into a tiger[44]
  • Tile: Projects antimagic shell around user; stone turns to dust when used[15]
  • Tredyhedron: +1 to Wisdom[15]
  • Triclinid: +1 to saving throws vs fire[15]
  • Tubule: Grants infravision with a range of 60 feet[15]
  • Vibrant purple prism: "Reserve"; a rare ioun stone which stores three levels of spells, as a ring of spell storing, minor[31][2]
  • White and pink rhomboid: "of Perfect Language"; understand all spoken languages, +5 to Charisma-based skills[39]
  • Yellow sphere: Sheds continual light on command[5][12]
  • Yellow spindle: +1 on saves vs petrification[24]

Related items and spells

Other items exist which orbit the bearer's head in the manner of an ioun stone. These include the mantle stone of Vhyridaan, a sentient crystal;[45][46] the Abyssal Shard, a dark artifact formed of elemental chaos;[47] and the golden orb of Siluvanede.[48]

Fragments of the gem of harmony, if shattered, absorb enchantment spells. When burned out, they become valuable diamonds.[49]

Ioun stones are sometimes pressed into another magic item to draw on their power. The lich priestess Vermissa possesses a gold and amethyst magical earring crafted from an ioun stone, which can absorb 58 spell levels.[50] The Wyvern Crown of Cormyr has ten functioning ioun stones mounted in it.[25] Factol Darius the Veyl possesses an ioun stone bracelet which stores spells, while Erin Darkflame Montgomery has a purple ioun stone set in a silver tiara.[51]

The ioun blade is a dagger which can have an ioun socketed into the pommel, where it affects the wielder normally.[52] The thief Eldoriel owns a ring with a functional pale lavender ioun stone embedded in it.[53]

The gem of detection appears very similar to an ioun stone, but is highly polished and much smaller. These divination items are embedded into a chair or throne.[54]

Sages of Greyhawk suspect a possible common origin between the ioun stone and the dwaomer stones of the Cairn Hills.[55]

The spell Acererak's blackstone uses an ioun stone as a material component.[56] The spell warding gems causes gemstones to orbit the bearer's head in the manner of ioun stones.[57] Several spells, including stars of Arvandor and stars of Mystra, cause motes of light to orbit the caster's head like ioun stones.[58]

The spell false ioun stone can animated a gem as a temporary ioun stone.[59]

Publication history

Original D&D

The ioun stone first appeared in The Strategic Review #4 (Winter 1975), p.10. This article introduced nine ioun stones, most of which would later be changed from AD&D onward. In the following table, bold text represents elements of appearance which changed.

Effect Appearance Appearance (AD&D onward)
increases spell ability incandescent blue sphere None
increases Intelligence scarlet and blue sphere scarlet and blue sphere
increases Strength deep red sphere pale blue rhomboid
increases Constitution pink ellipsoid pink rhomboid
absorbs spells up to 4th level pink and green ellipsoid pale lavender ellipsoid
absorbs spells 5-8th level pale green ellipsoid lavender and green ellipsoid
sustains without food/water pale lavender spindle clear spindle
heal 1hp/turn pearly white prism pearly white spindle
store 2-12 spell levels clear prism vibrant purple prism

This article also introduced the idea used-up stones, recommending that ioun stones be randomly generated by rolling a d20 with 1-9 resulting in one of the nine stones mentioned, and a 10-20 generating a worthless dud stone.

Ioun stones are written in this article as "IOUN stones", as the name appears in Jack Vance's story Morreion.

Basic D&D

Ioun stones do not appear in the basic D&D product line which ran coterminously with Advanced Dungeons & Dragons.

AD&D 1st edition

The AD&D 1st edition Dungeon Masters Guide (1e) (1979), p.147, details fifteen types of ioun stone. Eight possess effects from the original nine from Strategic Review: incandescent blue sphere was dropped, scarlet and blue sphere was unchanged, and the remaining seven changed. The new stones were:

  • Incandescent blue sphere (increase Wisdom); a stone of this apearance previously increased spell ability instead
  • Deep red sphere (increase Dexterity); a stone of this apearance previously increased Strength instead
  • Pink and green sphere (increase Charisma)
  • Pale green prism (add one experience level)
  • Iridescent spindle (sustains without air)
  • Dusty rose prism (+1 "protection"; defined in A1-4 Scourge of the Slavelords (1986), p.107 as +1 to armor class and saves, but in other sources as only +1 to armor)

Additionally, the used-up stones were defined as dull gray in color, and of any shape, and given the additional effect of adding 10 points to psionic strength total.

Numerous AD&D products featured ioun stones. Since the fifteen ioun stones defined in the DMG were all of unique color, many were referred to simply by their color; e.g. "red ioun stone" (c.f. I12 Egg of the Phoenix (1987), p.14), rather than the full name of "deep red sphere".

The capitalization "ioun stone" is used in AD&D, rather than "IOUN stone" as in Vance's original work.

AD&D 2nd edition

The ioun stones of AD&D 1st edition also appear in the Dungeon Master Guide (2e) (1989), p.173 and Dungeon Master Guide (2e revised) (1995).

Ioun stones also appear in Dragon Annual 2 (1997), p.60-72, Encyclopedia Magica Volume Two (1995), p.613-618, and Netheril: Empire of Magic, Encyclopedia Arcana (1996), p.5-6.

Two major articles in Dragon #174 (Oct 1991), by Matthew P. Hargenrader introduce new ioun stones and expand upon the lore: Bazaar of the Bizarre: Ioun Stones: Where do you go if you want some more?, and The Dragon's Bestiary: Who guards the ioun stones? here are some candidates.

Further ioun stones are detaile in The Eyes Have It, Dragon #267 (Jan 2000), p.71.

Balian's yellow ioun stone appears in the 1993 TSR Trading Cards set as card 26 of 495.

HR3 Celts Campaign Sourcebook (1992), p.34 and HR7 The Crusades Campaign Sourcebook (1994), p.34, suggests that ioun stones would be unsuitable for D&D games in those settings.

D&D 3rd edition

Ioun stones appear in the Dungeon Master's Guide (3.0) (2000), p.220 and Dungeon Master's Guide (3.5) (2003), p.260-261. Additional stones appear in various sourcebooks, including Ghostwalk (2003), p.72, Expanded Psionics Handbook (2004), p.160, Lords of Darkness (3e) (2001), p.161-162, What's in a Magic Item?, Dragon #311 (Sep 2003), p.18, and I Scry: Spying and Divination Magic Items, Dragon #319 (May 2004), p.64.

D&D 4th edition

Ioun stones appeared in D&D 4th edition as a head-slot magic item. Their invention is retroactively attributed to Ioun, a deity of knowledge and prophecy who appears throughout this edition. Ioun stones are now primarily designated by names rather than color; for example, the iridescent spindle ioun stone is referred to as the Ioun Stone of Sustenence.

Ioun stones appear in the Player's Handbook (4e) (2008), p.249, Adventurer's Vault (2008), p.143-144, Adventurer's Vault 2 (2009), p.28, Manual of the Planes (4e) (2008), p.156, Mordenkainen's Magnificent Emporium (2011), p.69-70, and Open Grave (2009), p.38-39.

D&D 5th edition

Ioun stones appear in the Dungeon Master's Guide (5e) (2014), p.176-177. All-new stones appear in Infernal Machine Rebuild (2019), p.94 and Lost Laboratory of Kwalish (2018), p.55.

The 5th edition DMG continues the 4th edition lore, which is that the stone is named for the deity Ioun. As a result, the item's name is capitalized, i.e. "Ioun stone", as Ioun is a proper name. It does not specify whether or not Ioun himself created them.

Creative origins

The ioun stone originally appeared in the short story Morreion by Jack Vance, published in the fantasy anthology Flashing Swords! #1 (1973). Morreion was later collected in Vance's anthology Rhialto the Marvellous (1984).

According to The Strategic Review #4 (Winter 1975), p.10, which debuted the ioun stone as a D&D magic item, Vance gave permission for the ioun stones' inclusion in that issue. They were originally referred to as "IOUN stones", a capitalization which also occurs in Morreion.

Gary Gygax cited both Jack Vance and Flashing Swords editor Lin Carter in Appendix N, a list of authors whose works were highly influential to early Dungeons & Dragons. Vance's Dying Earth series is also the inspiration for D&D's Vancian magic system.

Reception and influence

The inclusion of ioun stones in the core rulebooks of AD&D 1st and 2nd edition and D&D 3rd, 4th and 5th editions has inspired numerous newly invented ioun stones in sourcebooks and adventure modules. In addition to the 150+ ioun stones appearing in canonical works as listed above, numerous third-party publications have introduced new ioun stones, including Pathfinder RPG, Kobold Quarterly #6, The True Arcane Story: Ioun Stones, and Spells & Spellcraft by Fantasy Flight Games.

D&D creator Gary Gygax used ioun stones in his D&D games. In What's in a Magic Item?, Dragon #311 (Sep 2003), p.18, he tells a story of Melf, a gray elf character played by his son Luke Gygax, then in his teens. Melf reached 12th level as a magic-user, the maximum allowable character level for that class and race combination at that time. However, he was able to reach 13th level by acquiring an ioun stone which raised his magic-user level. This may have been the pale green prism ioun stone, which the Greyhawk character Otiluke (also played by Luke Gygax) is said to possess in The City of Greyhawk, Greyhawk: Folk, Feuds, and Factions (1989), p.25.

In Sage Advice, Dragon #58 (Feb 1982), p.28, Skip Williams gives a contrary opinion, that an ioun stone is not powerful enough to exceed level limits in this manner. This is countered by Polyhedron #15's Dispel Confusion column, which argues that ioun stones are very powerful and can exceed normal limits.

In Bazaar of the Bizarre: Ioun Stones, Dragon #174 (Oct 1991), p.90-94, author Matthew P. Hargenrader argued that ioun stones are potentially one of the most powerful types of magic items. He believed the notion of powerful human wizards simply crafting such items "lacks any spirit of adventure".

In Dragon #247 (May 1998), p.22, Skip Williams tells a story of a campaign in which his character found a set of ioun stones, but they were coated in contact poison which proved too difficult to remove. When two dragons interrupted his cleaning attempt, he slew one by throwing a poisoned ioun stone down its throat.

References

  1. Ay pronunseeAYshun gyd, Dragon #93 (Jan 1985), p.26.
  2. 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 Dungeon Master's Guide (5e) (2014), p.176-177.
  3. 3.0 3.1 The City of Greyhawk, Greyhawk: Folk, Feuds, and Factions (1989), p.25.
  4. WGR3 Rary the Traitor (1992), p.12.
  5. 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 5.11 5.12 5.13 5.14 5.15 5.16 5.17 5.18 5.19 5.20 5.21 5.22 5.23 5.24 5.25 5.26 5.27 5.28 5.29 5.30 Bazaar of the Bizarre: Ioun Stones, Dragon #174 (Oct 1991), p.90-94.
  6. Dungeonscape (2007), p.38.
  7. Bazallin's Blacksphere, Error: No such issue.
  8. Core Beliefs: Wee Jas, Dragon #350 (Dec 2006), p.28.
  9. Dragon #363 (Apr 2008).
  10. Volo's Guide to All Things Magical (1996), p.36-49.
  11. Races of Faerûn (2003), p.52.
  12. 12.00 12.01 12.02 12.03 12.04 12.05 12.06 12.07 12.08 12.09 12.10 12.11 12.12 12.13 12.14 12.15 12.16 12.17 12.18 12.19 12.20 12.21 12.22 12.23 12.24 12.25 12.26 12.27 12.28 12.29 12.30 12.31 12.32 12.33 12.34 12.35 Encyclopedia Magica Volume Two (1995), p.613-618.
  13. 13.0 13.1 13.2 Netheril: Empire of Magic, The Winds of Netheril (1996), p.5-6.
  14. 14.0 14.1 The Grand History of the Realms (2007), p.28.
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