Demonologists work magic that is very similar on a practical level to that of typical mages, but which is tainted by evil and powered by demons or other malevolent supernatural forces. Demonology can sometimes be learned through study of forgotten grimoires, but most accomplished Demonologists were directly taught the majority of their skills by a demon or devil of some kind. Almost every society has a terror of, and loathing for, Demonology and its practitioners, at least officially.
As well as casting Demonology spells, Demonologist are known for summoning and commanding demons. Demons despise, or at best envy, their summoners, but are bound by contracts to do their bidding. Most love to be summoned (so that they can bring chaos to the world) but hate being bound. Since they serve against their will, demons will almost invariably attempt to do the minimum amount of work possible to fulfill the letter of the contract and, if at all possible, will pervert the intent of the contract so as to actively cause problems for the summoner.
Summoning rituals work similar to spell rituals and can be found as can ritual spells.
The use of Demonology is inherently corrupting to the Demonologist’s mind, body, and soul, but particularly the soul. The Gamemaster will record all the instances a character uses Demonology – this number is the number of Corruption Points the character has. No distinction is made between spells used for good or evil. Even the spells that destroy demons draw on corrupting energy to perform them. The total amount of corruption points gained over the character’s lifetime is compared to the Demonic Corruption Table, to determine how corrupted the character has become.
While it is possible for a Demon to form a body for itself when summoned on the Earthly plane, it is easier for it to possess someone else’s. This also gives the demon a disguise to use when working its mischief. When a demon possesses another creature, it takes complete control of his body. If the ‘host’ body dies, the demon must successfully possess a replacement body within a short period of time, or else be forced back to its home plane. The Demon can decide to incarnate a physical form during this time, but it is costly for it to maintain the incarnated form.
Conjuration/Summoning Magics and Demonology
The use of conjuration and summoning magics is a rare and oft maligned specialty. The conjuration of goods and materials by raw magical effort is rarely practiced by wizards, and spells from this underdeveloped field of research are few and scarce. Most wizards are content to work with existing materials, enhancing and transforming them with magic. Likewise, summoning is rarely practiced openly as this art has long been linked with demonology, and seems to draw unwanted demonic attention even in cases where the summoner is not attempting to contact those foul otherworldly beings.
Every time a character cast a conjuration spell there is a chance that a fiendish creature will notice the spellcasting. In many cases the fiend will mark the character and subject him to continued scrutiny. If the fiend’s interest is piqued, it may begin to tempt the character with dream-sendings, offerings of power, rare spells, or other enticements. A character thus marked will be noticed by a paladin’s divine sense (though the paladin doesn’t distinguish a mark, just that the person is fiendish).
Celestials and Fiendish creatures summoned are not bound by the spells unless the creature is summoned into a magic circle and even then the caster must make a contested level check or the creature will break free through a mistake in the circle or by trickery.
The following spells are not subject to the above noticement by fiendish creatures, whether this is because the spells are beneath their notice or because they are in actuality transmutation spells is unclear, but the fact remains that they appear to be safe to cast: call lightning, ensnaring strike, entangle, grasping vine, hail of thorns, mage hand, grease, fog cloud, sleet storm, mass heal.