why the mountain above Ballachulish is literally called Hill of the Beast

Beinn a' Bheithir. Gaelic, means mountain of the beast / thunderbolt, sits right over Loch Leven by Ballachulish. Not a fairy story name slapped on later — the dragon's in the name itself. She holed up in Corrie Liath, a great hollow on the face, right above where the pier is now, and she'd watch th……