This spell was almost identical to find familiar, except it could only be cast be necromancers. Using this spell, a caster could gain a familiar of only certain species. These species were: a bat, a black cat, a frog, a giant centipede, a giant rat, an imp, a large spider, a quasit or a raven. Imps and quasits would only become familiars to a powerful necromancer. If the familiar was killed, the caster suffered extreme pain.
In addition to verbal and somatic components, the spell required material components, which were the same as the find familiar spell: a high-quality charcoal, incense and herbs that needed to be burned in a brazier made of brass as part of the ritual. These materials cost at least 2,000 gp. The caster was only able to cast this spell once a month, during a full moon.