Dungeons & Dragons has hundreds of unique and powerful monsters for Dungeon Masters to challenge their players with throughout their adventures. Though D&D has plenty of monstrosities, undead, and beasts, its devils are some of its most exciting foes. These fiends are generally lawful evil, hellbent on conquering and dominating other creatures and even their own kind.
Source:https://www.cbr.com/dungeons-dragons-types-of-devils-how-to-use-them-properly/