The Thrice-Blessed Sword
The Autumn Blade, also known as the Thrice-Blessed Sword or, formerly, the Blade of Gwrtheyrn, is a relic, an enchanted sword forged in the court of ancient Lyonesse to be the personal blade of Prince Gwrtheyrn, made with a keen and unfailing edge and able to hold and channel magic with great power. When Gwrtheyrn's stepson, who would become known later as Rey Devoss, was taken by the Morrígan to Faërie, the prince asked favor of the goddess, requesting that she keep the blade and, one day, pass it on to the boy. The goddess consented, and moreover she gave the blade blessings of her own, imbuing it with the magic of the Tuatha Dé Danann, making the blade effectively indestructible. In time, it was passed on to Rey, who spent years among the fae.
At the court of The Erlking, the sword was blessed a third time, awakening its inherent ability to channel magic. From then on, the blade was able absorb magic effects up to a superlative level. This does have limitations, as it can only absorb a single active effect at a time, and the effect must be reasonably localized. More minor effects may be absorbed over a larger area, but for each absorbed effect, the sword gains power. So, if it absorbs multiple Enhanced effects or a single Supreme effect, it may gain a few minutes of attack power at that level. If it absorbs multiple such effects in a row, its strength might last longer. Notably, it takes a great deal of concentration to absorb such effects, so the wielder may not be doing much else at the time that would distract them.
The Autumn Blade, before it was given a proper name, was previously known as the Blade of name Gwrtheyrn. Gwrtheyrn is a modernization of the Old Welsh, Guorthigern, composed of the elements gor "over" and tigern "king, lord," hence "high lord" or "overlord, which is the best available translation from the original name, which was in the language of Lyonesse. Gwrtheyrn, it should be noted, was also a variant on the name of King Vortigern of Arthurian Legend--this was a different person entirely.