St. Patrick didn’t just drive snakes out of Ireland, he had to deal with their demonic fire-breathing momma, too. Legend has it that Caorthannach was the mother of all demons, hatched deep inside the molten core of Earth at the beginning of time.

Once her children were grown and ready, she set them loose on the world in the form of snakes, with the instruction to bring chaos and evil wherever they went. So, when St. Patrick cleansed the island of snakes, Caorthannach wasn’t best pleased. The two battled it out atop a mountain for two days and two nights. The story diverges into different versions here: in one, Caorthannach is banished into a water cave, while in another, she devours Patrick, only for him to slice her open from the inside.