Twrch Trwyth

Twrch Trwyth (; also Trwyd), is a fabulous wild boar from the Legend of King Arthur, of which a richly elaborate account of its hunt described in the Welsh prose romance Culhwch and Olwen, probably written around 1100. Its hunt involved King Arthur and his hosts and his hound Cafall, and was also deemed to require other recruited men of talent, other hounds, and additional equipment such as leash, according to the tasks (anoetheu) prescribed by the giant Ysbaddaden, though events did not always unfold as the giant foretold. The boar was brought out of Ireland, driven to Britain, and finally shoved off the cliff into sea at Cornwall. The legend, in simpler form, dates much earlier, since Arthur's use of his hound Cavall (Cavall (base text, MS. MS. H), caball (MS. K), caballusMS. D1), caballus(MSS. D2 G) to hunt the boar (Troynt (base text, MSS. H K), Troit (MSS. C1 D G Q); or Terit (MSS. C2 L)) is glimpsed in a piece of geographical onomasticon composed in Latin in the ninth century, the Historia Brittonum. A passing reference in the elegy Gwarchan Cynfelyn (7th century), preserved in the Book of Aneirin, reckoned to be its earliest mention in literature. Refn|Lady Guest (1849) had noticed this occurrence. The name in Welsh can be construed to mean "the boar Trwyth", and past scholars argued it may be analogous to the boar Triath of Irish mythology (see #Etymology and Irish cognate below).

As previously noted, the Welsh word twrch means "wild boar, hog, mole", so Twrch Trwyth means "the boar Trwyth". Its Irish cognate may be Triath, King of the Swine or the Torc Triath mentioned in Lebor Gabála Érenn, also recorded as Old Irish Orc tréith "Triath's boar" in Sanas Cormaic; John Rhys was conducive to the idea that these Old Irish words or names had been borrowed by Welsh literature and recorded as Trwyth or Trwyd. However, Rachel Bromwich took a position contrary to Rhys, and was skeptical that there should be any reason to conclude there had to be any mutual borrowing between the Irish and the Welsh regarding the boar names. Bromwich regards the form Trwyth as a later scribal corruption and asserts trwyd to be the "original form"; also, the misreading of d with t in Welsh Trwyd, together with vowel shifts by copyist led to the Latinised forms Troynt or Troit. Further evidence that Trwyd was the original correct form is found in the aforementioned reference in the Gwarchan Cynfelyn and later poetry.

It has been suggested that Trwyth the boar has been remolded as a human character or reconfigured into another boar in French romances. The Knight of the Round Table named "Tor son of Ares" who appears in Chrétien de Troyes's romance Erec et Enide may have been reinvented out of "Twrch son of Tared" in Culhwch ac Olwen, an idea advanced by Idris Llewelyn Foster Some scholars venture that the authentic patronym in the original lore gave the father's name as closer to "Ares". Another suggestion is that Trwyth was recast as a different in the story of Caradoc (another Knight of the Round) in the so called Livre de Caradoc of the First Peceval Continuation. Here, Cardoc is angered to discover he was in fact illegitimate, a product of cuckoldry, and punishes the wizard who was his biological father by forcing him to mate with a mare, a greyhound, and a sow, each producing an offspring that became Cardoc's brothers. Y Twrch Trwyth is also the mascot of Ysgol Dyffryn Aman (formally Amman Valley Comprehensive School and Amman Valley Grammar School) in Ammanford, Carmarthenshire, South West Wales. In the 2016 summer event of the mobile game Fate/Grand Order, Twrch Trwyth is the final boss.