Summon Demon

Special 
This version of Planar Summons raises demons; see that spell description for details. If the caster fails to control the demon, it always attacks him! If it cannot reach the caster (if, for example, the caster is protected by a Pentagram), the demon will vanish (if trapped) or escape to wreak havoc in the outside world. 
If he manages to control the demon and give it a command, the demon will carry out the letter of its orders, doing its best to pervert their spirit to the caster’s disfavor. It will also work incidental mischief, unless specifically instructed not to. 
At the GM’s discretion, a caster may summon a flock of minor demons whose values add up to 200 character points or less (a caster summoning minor demons may never spend more than 20 energy on this spell). In this case, the caster controls the entire flock at once, contesting the highest Will in the flock. A flock of minor demons is not restrained to a single task; they always stay for the entire duration of the spell.

Duration: Until the demon’s task is done, or one hour, whichever is less. 
Cost: 1 point per 10 character points used to build the demon. Minimum energy cost is 20 (although this will not always summon a 200-point being). Those tempted to summon powerful demons should bear in mind that such demons tend to have high Will, with all that implies for control . . . 
Time to cast: 5 minutes. 
Prerequisites: Magery 1 and at least one spell from each of 10 different colleges.

Item 
Certain artifacts are known to make summoning (or summoning a particular demon) easier. Those who deal with demons prize such items, but (fortunately!) the technique for making them is not commonly known.

Black Critical Table 
After any failure using demonically assisted magic, the GM rolls 3d on the table below. Use these results as guide-lines; improvise wildly to customize the awfulness and to convey the prickly uncertainty of demonic aid. A failure should never result in the caster’s intended effect, or even accomplish it accidentally.

Failure Effect

Roll Description
3 Spell appears to work, but is only a useless illusion.
4 Spell fails entirely. Somewhere else, demonic “backblast” does something awful to something the caster values; the level of awfulness varies with the power and intent of the spell.
5 Caster loses one level of Will.
6 Caster loses one level of Appearance in a manner appropriate to the spell attempted. A Create Fire spell might cause unsightly burn scars, while a Madness spell might subtly unhinge the caster’s eye sockets for a wild, staring effect.
7 Spell is cast on loved ones, friends, allies, innocent bystanders, or the caster (in that order) if malevolent, on foes if benevolent.
8 Spell fails entirely; caster takes 2 points of injury and the wound immediately becomes infected (see Infection, p. B444).
9 Caster must make a Fright Check at -5 as horrific visions of the hells fill his eye sockets.
10 Spell does nothing except drench the room in a conspicuous odor of brimstone centered on the caster.
11 Spell produces the reverse of the intended effect.
12 Spell produced the reverse of the intended effect, on a random friendly or neutral target.
13 Spell fails entirely; caster takes 1 point of injury as his arms erupt in boils.
14 Spell fails entirely; room fills with buzzing insects pouring from caster’s mouth.
15 Spell creates vermin (rat, giant cockroach, immense tapeworm) inside the caster (stomach, throat, etc.). Depending on the nature and location of the vermin, this may do severe damage; an agitated rat in one’s innards would do up to 2d damage directly to the vitals!
16 Spell withers caster’s hand.
17 Spell fails entirely; caster ages 4d years.
18 Spell fails entirely and summons a different demon who attempts to wreak havoc (attacking the caster if he gets in the way). The mage may use black magic to fight this demon; demons will happily fight each other.