A hellion (憑魔 hyouma?, "possessing evil") is a type of creature in Tales of Zestiria. Hellions are created from malevolence, impurities born from the negative emotions of humanity, and threaten the existence of humans and seraphim.
The Lord of Calamity is a being that gives rise to the hellions. They cannot be seen by normal human eyes, and humans and animals possessed by the malevolence appear to them as if they were normal. Seraphim and humans with high spiritual energy are able to see hellions, which can take on a variety of forms, such as slimes and human-animal hybrids. Only a few beings are able to deal with hellions; a Shepherd typically wields the power to purify them, and certain Fire seraphim such as Lailah wield the flames of purification. Zaveid also possesses an unique firearm called "Siegfried" capable of killing hellions, which is different from purifying them. It is not known what happens to hellions that are defeated in combat without either the means to purify or kill them, but numerous seraphim can at least do that much. Presumably, they recover quickly.
- Hellion is an alteration of the word Hell, which is depicted as a place of eternal torment in many mythological, folklore, and religious traditions. The word hellion means "an unruly, rowdy or mischievous person" or "an evil person", fitting for their role in the game.