Devils are the true incarnation of patient evilness, tempters that corrupt the heart of mortals and constantly plot infernal schemes to bring ruin and despair into the world. From their homeland of the Nine Hells of Baator, they battle constantly against each other, ruled by the Archdevils and the most ancient of them, the now ascended devil god Asmodeus.
Devils all adopt nightmarish appearances; they strive after men's hearts, trading souls for power in exchange for favors and positions of authority in the infernal hierarchy. Devils possess spell-like abilities which they use to deceive and confuse their enemies, relying also on their infernal claws and weapons to slay their opponents.
Devils are not usually found in the land of the Forgotten Realms. When they are, it is because they have been summoned by an evil warlock or decadent priest hoping to establish and control a cult around them. These alliances often turn sour for the summoner. Devils almost always get the upper hand in a bargain.