Math fab Mathonwy

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Edward Matthew Ward (1816-1879), "King Lear and Cordelia"

Edward Matthew Ward (1816-1879), "King Lear and Cordelia"

From Wikipedia, the free encyclopedia

In Welsh mythology, Math fab Mathonwy, also called Math ap Mathonwy (Math, son of Mathonwy) was a king of Gwynedd who needed to rest his feet in the lap of a virgin unless he was at war, or he would die. The story of Math is the fourth book of The Four Branches of the Mabinogi.

The Mabinogi of Math

Math is tricked by his nephews

Math's nephew Gilfaethwy had fallen in love with Goewin, Math's footholder. The magician Gwydion (Gilfaethwy's brother), devised a plan to make Goewin available. Gwydion told his uncle about an animal that was new to Wales, called pigs, and how he could get them from their owner, Pryderi of Dyfed. He took a band of men, including his brother, to Ceredigion, where they disguised themselves as bards to gain audience with King Pryderi.

Gwydion was a skilled cyfarwydd (storyteller) and regaled the court with his tales. Having charmed the king, he offered to trade the pigs for some horses and dogs, which he had conjured through magic. Pryderi agreed to the trade and Gwydion and his men took the pigs back home to Gwynedd, but his trickery was revealed and Pryderi waged war against Gwynedd. While Math went to battle, Gilfaethwy raped Goewin.

The war ended when Gwydion killed Pryderi in single combat. Upon his return to his castle, King Math went to rest his feet in Goewin's lap, but could not, as she was no longer a virgin. He took her as his wife to save her honor, and then as punishment, banished his nephews, turning them into a breeding pair of deer for a year. He then turned them into wild boars for the next year and wolves the year after that. They had three children over the three years: Hyddwn, Hychddwn, and Bleiddwn.

Gwydion and his nephew

After their punishment was over, Math asked their advice as to who should be his next virgin footholder. Gwydion suggested his sister, Arianrhod. However, Arianrhod was not a virgin and when asked to step over Math's rod in order to prove her virginity she immediately gave birth to a son. Abandoning the child she fled in shame, letting drop a "lump of flesh" which was born away by Gwydion and concealed in a chest. When Gwydion later opens the chest he discovered the lump of flesh to be a second child.

Meanwhile the firstborn son of Arianrhod was acknowledged by his great uncle Math and given the name Dylan upon baptism. However, as soon as Dylan came in contact with his baptismal waters, he plunged into the sea and took on characteristics of a sea creature, moving through the seawater as perfectly as any fish, thus earning his epithet, Eil Ton ‘the son of the wave’:

‘So they had the boy baptized, and as they baptized him he plunged into the sea. And immediately when he was in the sea, he took its nature, and swam as well as the best fish that was therein.'

The unnamed second child grew precociously and he and Gwydion grew very attached to one another. After four years Gwydion took the boy to see his mother, who refused to recognise him out of shame and anger that Gwydion should have nurtured the boy, and placed a tynged on him that he should have no name unless she gave it to him. To trick her into naming him, Gwydion disguised himself and the boy as shoemakers and as they were making shoes for her, the boy threw a stone at a bird and killed it. Arianrhod declared "The fair one struck with a deft hand", and thus he was named Lleu Llaw Gyffes ("Fair-Haired One of the Skillful Hand").

His trick revealed, Arianrhod placed a tynged on the boy again that he would not take up arms until she gave them to him. Time passed and Lleu grew big and strong. Again, Gwydion disguised his nephew and himself, this time as bards, and like he did to King Pryderi, entertained Arianrhod's court with stories. In the morning, Gwydion deceived Arianrhod to believe that her estate was under attack. When she asked for his advice, he bade her gird a sword on Lleu Llaw Gyffes, whom he said was a skilful fighter. No sooner had she done so, than Gwydion revealed the truth.

Furious at being tricked again, Arianrhod placed a tynged on her son once more, that he would never have a human wife. By this time, Math had come to sympathize with Gwydion. Together, the Wizards created a woman from the flowers of the oak, of broom and of meadowsweet and brought her to life, giving her the name Blodeuwedd ("Flower Face").

Lleu and Blodeuwedd

One day, when Lleu was away from home visiting Math, Blodeuwedd saw a nobleman, named Gronw Pebr, passing and invited him to stay (for it would be rude not do so). They fell in love and concocted a plot to kill Lleu. Blodeuwedd found out from Lleu how he could be killed — with one foot on the back of a buck and the other on a bath of water, underneath a canopy, using a spear that had been made over the course of a year only on Sundays. She told this to Gronw and he set out to make the spear.

A year later, she persuaded Lleu to demonstrate this odd position where he might be killed. Suspecting nothing, he did so. Gronw, who had been waiting in ambush, threw the spear he had made at him. However, rather than dying outright Lleu turned into an eagle and flew away wounded. Gronw then took Blodeuwedd and Lleu's land. Gwydion went searching for his nephew and, by following a pig, found him (still an eagle) in a very bad state at the top of an oak tree by a lake. He called him down from the tree with three stanzas of poetry called englyn Gwydion, transformed him back into a man and with Math nursed him back to health. Then Lleu sought revenge on Gronw and his wife.

Blodeuwedd heard of this and fled, taking her maidens with her, but they were so frightened, that they ended up walking backwards to make sure nobody attacked them from behind. Unfortunately, they ended up falling into a lake, with only Blodeuwedd surviving. Gwydion captured her and instead of killing her, turned her into an owl.

Gronw offered Lleu land or money as payment, but Lleu would only accept one resolution: that he throw a spear at Gronw in the same way that he had been attacked. Gronw accepted, but asked that a large stone be placed between him and Lleu. Nevertheless, Lleu threw the spear right through the stone and killed Gronw. After this he took back his lands and later succeeded Math as king of Gwynedd.

Role-playing Notes

Intermediate god

Math Mathonwy is the god of sorcery. He carries a mighty magical staff and wears a torc given to him by the other gods. As master of his household, Math insists that his feet rest in the lap of a maiden whenever possible. He does not tolerate mistreatment of his maiden foot warmers, nor does he abide treachery on their part, and has vented his wrath upon many who have violated his trust. He saves his magic mainly for his own purposes, keeping his family in check, and seldom casts spells for the good of his followers or priests.

Math Mathonwy seldom goes into the world of men without some mission. It is rare that he will become embroiled in the affairs of humans unless there is some magical experimentation involved. Math Mathonwy is always in search of new magics and humans knowing this can trick his avatar into action, but they might suffer his wrath at a later time.

Originally written by

Dom of D20 / D&D 3e Netbooks and Downloads.

On this Link

Math Mathonwy
The Miser of Sorcery
Intermediate Celtic Deity

Symbol: A magical staff. Filidh of Math must have a magical staff as their holy-symbol. This staff may be a true magical item or simply a normal staff upon which some enchantments have been wrought. Then, this staff is consecrated as their Holy symbol during a special ceremony.
Home Plane
Neutral Evil
Portfolio: : Secret knowledge and magic.
Worshippers: Wizards, sorcerer, loremasters.
Cleric Alignments: Any neutral
Domains: Evil, Greed, Knowledge, Magic, Mutation (new).
Favored Weapon: The staff
Special Benefit: Filidh of Math-Mathonwy who take the Loremaster prestige class, get a special "secret" ability of their own. That is, at 1st, 3rd, 5th, 7th, and 9th levels, instead of a normal "secret" they can choose three arcane spells that they will be able to get as divine spells (i.e.: they are added to the cleric spell list for that filidh). They can thus choose any spell they want on the wizard spell list, provided it is of a level equal or lower to the character's loremaster level (for example: a 7th-fili /2nd-lormaster can cast 5th level divine spells, but may only get 1st and 2nd level arcane spells to be available afterwards as divine spells). Once spells have been chosen, they cannot be changed thereafter.

Duties of priesthood: Filidh of Math-Mathonwy are expected to spend their time researching knowledge and magical things. As such, they will often travel to remote lands, mysterious place, or The Otherworld, as a way to gain more knowledge of the occult. On the other hand, they have no obligations concerning the mundane affairs of the Celtic society, and seldom participate into its religious rites. They nonetheless share their discoveries with the Druidical order, of which they are the "college of magic".


Originally Posted by

Tebryn14 of the Wizards Community forums.

On this Thread

Math-Mathonwy is the reclusive Celtic god god of magic and sorcery, who introduced wizardry to the Celtic lands. He is primarily interested in his researches on the occult and magic, and seldom intervenes in the affairs of the others. The only exception of this seclusion is to avenge himself of those who try to take advantage of him. Math is told to live in a great magical castle, served by a host of Sidhe women, all of whom must be virgins.

A powerfully magical being, he greedily hoards his powers, only using his magic for the good of his family, completely ignoring his followers, servants, and whatever may pass for his friends. However, he is intensely curious about any new magical secret, and may, if swayed, share some of his secrets in return. Mathonwy appears as an elderly man in a heavy tunic and robes.

Wizard 20/Cleric 7/Mystic Theurge 10/Archmage 5

Medium-Size outsider (Evil, Extraplanar)

Divine Rank


Hit Dice

20d8+160 (outsider) plus 20d4+160 (wizard) plus 7d8+56 (cleric) plus 10d4+80 (mystic theurge) plus 5d4+40 (archmage) (852 hp)




60 ft.


69 (+14 divine, +9 Dexterity, +27 natural, +9 deflection)

Base Attack/Grapple



+6 quarterstaff +68/+63/+58/+53 melee; or by spell +63 melee touch, or +65 ranged touch.


+6 quarterstaff 1d6+16+transformation into water; or by spell.


5 ft. by 5 ft./ 5ft.

Special Attacks

Domain powers, salient divine abilities, spell-like abilities, rebuke undead 12/day, arcane fire (600 ft., 5d6+1d6spell level).

Special Damage

Arcane reach, mastery of counterspelling, mastery of elements, spell power +1, divine aura (1,400 ft., DC 33), divine immunities, DR 25/epic, familiar (rats), fire resistance 19, godly realm (10 miles), plane shift at will, greater teleport at will, remote communication 14 miles, spontaneous casting of divine spells, SR 66, understand, speak, and read all languages and speak directly to all beings within 14 miles.


Fort +55, Ref +56, Will +59


Strength 24, Dexterity 28, Constitution 26, Intelligence 46, Wisdom 32, Charisma 29.


Appraise +76, Bluff +45, Climb +37, Concentration +92, Craft (Alchemy) +92, Decipher Script +78, Diplomacy +67, Gather Information+65, Heal +45, Hide +63, Intimidate +43, Knowledge (Arcana) +97, Knowledge (Architecture and engineering) +84, Knowledge (Geography) +84, Knowledge (HistoryHistory) +90, Knowledge (Nature) +84, Knowledge (Nobility and royalty ) +84, Knowledge (The Planes) +92, Knowledge (Religion ) +96, Listen +70, Move Silently +63, Search +75, Sense Motive +73, Spellcraft +101, Spot +70, Use Magic Device +43. *Always receives a 20 on checks.


Alertness, Brew Potion, Craft Construct, Craft Magic Arms and Armor, Craft Rod, Craft Staff, Craft Wand, Craft Wondrous Item, Dodge, Empower Spell, Enlarge Spell, Extend spell, Forge Ring, Heighten Spell, Greater Spell Penetration, Improved Initiative, Iron Will, Maximize Spell, Quicken Spell, Silent Spell, Skill Focus (Spellcraft), Spell Mastery, Spell Penetration, Still Spell, Weapon Focus (ray).

Divine Immunities

Ability damage, ability drain, acid, cold, death effect, disease, disintegration, electricity, energy drain, mind-affecting effects, Paralysis, poison, sleep, stunning, transmutation, imprisonment, banishment.

Salient Divine Abilities

Alter Reality (DC 43 for duplicated spells), Arcane Mastery, Automatic Metamagic (quickened Wizard Spells), Automatic Metamagic (Silent Wizard Spells), Avatar (10), Clearsight (140 ft.), Craft Artifact, Divine Blast (12/day; 23d12 points of damage; 14 miles), Divine Shield (11/day; 140 points of damage); Divine Spellcasting, Extra Domain (Magic), Extra Domain (Spell), Increased SR, Instant Counterspell, Know Secrets (DC 33), See Magic, Spontaneous Wizard Spells.

Domain Powers

cast evil spells at +1 caster level; +2 bonus to Appraise , Open Lock, and Slight of Hand checks; cast divinations at +1 caster level; use spell completion and spell trigger items as a Wiz 38; +2 bonus on Spellcraft and Concentration checks.

Spell-like Abilities

Mathonwy uses these abilities as a 24th level caster, except for evil and divination spells, which he uses as a 25th level caster. The save DCs are 35+spell level. protection from evil, desecrate, magic circle against good, unholy blight, Dispel Good, create undead, blasphemy, unholy aura, summon monster IX*, Cheat, Entice Gift, knock, fire trap, fabricate, guards and wards, teleport object, Phantasmal Thief, sympathy, detect secret doors, detect thoughts, clairaudience/clairvoyance, Divination, true seeing, find the path, Legend Lore, discern location, Foresight, Undetectable Aura, identify, Dispel magic, imbue with spell ability, Spell Resistance, antimagic field, spell turning, protection from spells, mage's disjunction, mage armor, silence, Anyspell, mnemonic enhancer, Break Enhancement, Greater Anyspell, limited wish.
*Cast as an evil spell only.

Cleric Spells/Day

6/8/8/8/7/6/6/5/3/2; base DC=23+spell level.
Wizard Spells/Day (Levels 0-18)4/9/9/8/8/7/8/5/6/6/4/3/3/3/3/2/2/2/2; base DC=30+spell level.

Possessions Mathonwy carries his staff, which acts as a +6 quarterstaff. In addition, any creature struck by it must succeed at a DC 55 Fortitude save or be permanently transformed into water.

Other Divine Powers

As an intermediate deity, Mathonwy automatically receives a die result of 20 on any check. He treats a 1 on a saving throw or attack roll normally and not as an automatic failure. He is immortal.

Senses Mathonwy can see, hear, touch, and smell at a distance of 14 miles. As a standard action, she can perceive anything within 15 miles of her worshippers, holy sites, objects, or any location where one of her titles or name was spoken in the last hour. She can extend her sense to up to ten locations at once. She can block the sensing power of deities her rank and lower at up to two remote locations at once for up to 14 hours.

Portfolio Sense Mathonwy senses any use of magic by a worshipper of a Celtic deity the instant it happens and retains the sensation for 15 tendays. He likewise senses any magical discovery made by such a person.

Automatic Actions Mathonwy can use any Knowledge skills, Concentration , or Spellcraft as a free action as long as the DC is 25 or lower. He can perform up to 10 such free actions each round.

Create Magic Items Mathonwy can create any magic item as long as the market price does not exceed 200,000 gp.

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