Arch-fiends are often described as the most evil and malevolent beings in literature and mythology. However, there are also many words that can be used as antonyms for arch-fiends. These include terms like angels, saints, and saviors, which are often associated with goodness and purity. Other antonyms for arch-fiends might include fairies, sprites, and other magical creatures that are thought to be benevolent and protective. Ultimately, the word arch-fiends represents a powerful force of darkness and evil, and its antonyms can help to balance the scales and restore some hope and optimism to the world.