The Maleficium is a 1992 role-playing supplement for Ars Magica published by White Wolf Publishing.
The Maleficium is a supplement in which the Infernal is detailed.
Matthew Gabbert reviewed The Maleficium in White Wolf #37 rating it a 3 out of 5 and stated that "In summary all of the uproar surrounding The Maleficium is much ado about nothing. It is an average supplement that does a good job of dealing with a very difficult subject. Of course, there's always the chance that it could become a collector's item."