Horrortale Undyne is a character from the fan-made alternate universe of Undertale called "Horrortale." In this universe, Undyne is depicted as a more aggressive and menacing version of herself. She is known for her terrifying appearance, fierce determination, and a relentless pursuit of her goals. Horrortale Undyne embodies a darker and more sinister aspect of her original character, reflecting the eerie and unsettling atmosphere of the Horrortale universe.