I've been getting back into research recently for my next big project (Corruption & Concrete - Exiles Of Eire 3). Part of that research involves digging a lot deeper into the story of the Fomor King Balor of the Evil Eye.
According to myth, the Fomor were a race of evil giants who occupied Ireland. The nastiest of them was one of their kings, Balor, who was famous for the eye in the middle of his forehead that could scorch anything in its sight when it was opened. When Balor was a boy, he snuck up to watch his father's druids conjure a magical poison. Some of the toxic fumes seeped into his eye an changed it. One of the druids foretold that his daughter would have a son, who would kill him. From then on, he wielded his terrible new power against his enemies.
Off the coast of northern Ireland, a small place called Tory Island is where he kept his tower fortress. It's there where he imprisoned his only daughter and forbade any man to see her but him so he could cheat his ultimate fate.
Nice guy, huh?