Devilcats are a minor type of devil, often seen serving their infernal masters in the nine planes of Hell. Rarely, devilcats also travel to the Prime Material Plane to serve as a familiar for an important evil spell caster.

In normal lighting, devilcats are invisible. In total darkness however, they can be dimly seen as a glowing reddish aura resembling a large feline. Devilcats are immune to the effects of all charm, sleep, hold and suggestion spells. Further, they can only be harmed by magical weapons.

Devilcats encountered on the Prime Material Plane who are not already serving as a familiar may attach themselves to a suitable lawful evil character. They prefer to serve clerics, but will also attach themselves to a magic user or illusionist. If a stronger lawful evil character is present, devilcats will willingly switch to the new master, even betraying or attacking their former master in the process. In any case, a devilcat is only allowed to remain on the Prime Material Plane for a year and day. At the end of this period they must return to Hell. Sometimes they may later travel to the Prime Material Plane again, but will not necessarily seek out their old master.