Octriallach is a Legendary Fae and one of the dread Fomorians.
The Second Battle of Moytura
At the Second Battle of Moytura, Octriallach, the son of the Fomorian Indech, was not yet one of the potentates of the age, but was nevertheless clever and subtle, with a far-reaching eye for magic. When the Tuatha Ogma slew his father with a sword through the heart with the help of The Morrigan, Octriallach, swearing vengeance, turned into a white mist and fled into the Forest of Lies. The victorious Tuatha counted him among the dead; it was a mistake their changeling offspring would one day regret.
The War of Trees
Much later, the Fomorians returned and, with most of the Tuatha de Danaan gone, increasingly menaced the younger races. The conflict quickly escalated far beyond the scale set by the last war. The fae learned that Octriallach was not dead as once believed, but directing the cruelest of the Fomorian Courts from deep within Winterweir. A demon from the past had returned to haunt the world; Scathach’s duty was clear. Since no army could hope to defeat a creature like Octriallach, Scathach herself, one of the few remaining Tuatha de Danaan, despite her diminished blood, led a disparate contingent of nobles and commoners into the Winterwoods.
The sun did not shine in those woods, and a never-ending host of Dark-Kin, icy chimera, and invisible spirits harried the invading host. Warriors disappeared into this air, sometimes resurfacing as frozen, dismembered corpses. Still the diminished company eventually reached the forest’s chill heart and challenged the White King in his lair. Confident in his enemy’s doom, Octriallach himself joined the fray, determined to capture Scathach alive and force from her the location of his father’s blade, the Sword of Tethra.
The two met in single combat, and Scathach seemed a poor match for the White King, who warped and rent reality by his very presence. Bearing down upon his victim, the overconfident Fomorian did not notice how the Kithain’s most potent sorcerers had arranged themselves into a complex wizard’s knot around the battlefield, feeding their very life force into a fateful spell. The forest’s trees writhed like tentacles, enveloping the shrieking White Court and imprisoning them within, seemingly forever. The task of defeating the Red and Green Courts lay ahead, but the fae would have to accomplish this with little help from the Scathach. Scathach herself was gone, enshrined with her enemies at the heart of the Forest of Lies.