Spell-casting Insanity and Deamonic Possession

Divine Casters

Druids and Clerics begin each day with meditation or prayer, and channel the energy of life or their deity into specially prepared forms. Once crystallised into these forms they are hard to shape into new ones, but it can be done should the Cleric or Druid desire it. This process of reforming a spell causes some trauma to the casters mind however, and were one to do this frequently, they would risk insanity.

When a Druid or Cleric may cast a spontaneous spell that is not a domain spell or summon natures ally by taking insanity as below. This uses up a spell per day as if they had cast a spontaneous domain spell or summon natures ally. They may not therefore (unlike the Sorcerer or Wizard) continue casting after their spells per day have run out.

Arcane Casters

A Wizard prepares his defenses and mental structures each day in order to contain specific spells. He then channels arcane energy from the astral plane through these structures, and contained as such he risks not possession or insanity. However should a Wizard desire to do so, they can channel directly and immediately from the astral plane into a spell effect they desire. This could be a spell they had not prepared to cast this day, and one could continue to cast indefinitely, if it was not certain that they would go mad. If they were to survive the maddening effects of raw magic, they would risk and even greater ill. Such unprotected spell-casting shines out in the dark places of the void and the energy from the astral plane the Wizard channels become the entry way for daemons to enter her mind. Many a reckless Mage has known to have suffered such a fate, and the fate is certainly not pretty.

A Wizard may cast spells spontaneously by risking insanity and possession. Such castings do not use up his spells per day, but instead he gains insanity and risks possession.

While Sorcerer generates power inside themselves, as a product of their ancient bloodlines, they can like a wizard, bend reality to their will with the channeling of raw magic Like a Wizard however, this takes its toll on the mind of the Arcanist, and even reckless Sorcerers who pushes themselves too far over the borders of their own power have been known to have their bodies stolen, warped and twisted by the foulest of daemons.

When a Sorcerer has run out of spell slots they may choose to channel the energy of creation to bend reality to their will, rather than use their own inner force of will. As such if they run out of a level of spells per day, they may cast additional spells of that level by taking insanity and risking possession.


When casting a spell that gives a character insanity the insanity they take is determined per spell level multiplied by how many self-insanity causing spells they haves cast this day. They make a sanity check and passed they only take half this rounding down, if failed they take the full amount. Expressed as such;

Spell Level x No. Insanity Causing Spells this Day (SAN check for 1/2 Insanity points rounding down)

E.G. A caster who casts a level 5 spell (either spontaneous divine or wizard, or after exhausting all level 5 slots as a sorcerer) would take a sanity check.
If passed they would take 2 insanity points, if failed they would take 5 insanity points.
If they were to then cast another level 5 spell they would take another sanity test and take 5 points if passed or 10 points if failed.
If this second casting were to be of a level 3 spell then they would take a sanity test and take 3 points if passed or 6 points if failed.

If a Divine caster does this and takes more than half their wisdom from a single spell then they must roll on the temporary insanity effects table as per normal

However if they are an Arcanist they use the following rules for Sundering the Veil.


When an Arcanist takes more than half their wisdom score from a single spell then they risk Sundering the Veil. This is in effect opening their minds and risking possession.
Arcanists must keep track of how many Insanity points they have accumulated in a single day from this casting, as it effects their likelihood of possession.
When rolling to determine temporary insanity effects they use the following table, and increase the number rolled by the amount of insanity they have accumulated from spell-casting this day. The DM may make this roll in secret so the player does not know they are possessed if the daemon is particularly sneaky - it is however likely that a player will realised they are possessed when it occurs.

Duration of Temporary Insanity
d% (not including insanity modifier)
01–80 Roll on Short-term 1d10+4 rounds
81–100 Roll on Long-term 1d10×10 hours

Short-Term Temporary Insanity Effects
d% + Insanity from casting
01–20 Character faints (can be awakened by vigorous action taking 1 round; thereafter, character is shaken until duration expires).
21–30 Character has a screaming fi t.
31–40 Character flees in panic.
41–50 Character shows physical hysterics or emotional outburst (laughing, crying, and so on).
51–55 Character babbles in incoherent rapid speech or in logorrhea (a torrent of coherent speech).
56–60 Character gripped by intense phobia, perhaps rooting her to the spot.
61–65 Character becomes homicidal, dealing harm to nearest person as efficiently as possible.
66–70 Character has hallucinations or delusions (details at the discretion of the DM).
71–75 Character gripped with echopraxia or echolalia (saying or doing whatever those nearby say or do).
76–80 Character gripped with strange or deviant eating desire (dirt, slime, cannibalism, and so on).
81–90 Character falls into a stupor (assumes fetal position, oblivious to events around her).
91–96 Character becomes catatonic (can stand but has no will or interest; may be led or forced to simple actions but takes no independent action).
97-99 Roll on Long-Term Temporary Insanity
Effects Table
100 THE VEIL IS SUNDERED + generate additional Insanity Effect.

Long-Term Temporary Insanity Effects
d% + Insanity from casting
01–5 Character performs compulsive rituals (washing hands constantly, praying, walking in a particular rhythm, never stepping on cracks, constantly checking to see if crossbow is loaded, and so on).
6–15 Character has hallucinations or delusions (details at the discretion of the DM).
16–25 Character becomes paranoid.
26–35Character gripped with severe phobia (refuses to approach object of phobia except on successful DC 20 Will save).
36–40 Character has aberrant sexual desires (exhibitionism, nymphomania or satyriasis, teratophilia, necrophilia, and so on).
41–50 Character develops an attachment to a “lucky charm” (embraces object, type of object, or person
as a safety blanket) and cannot function without it.
51–60 Character develops psychosomatic blindness, deafness, or the loss of the use of a limb or limbs.
61–70 Character has uncontrollable tics or tremors (–4 penalty on all attack rolls, checks, and saves, except those purely mental in nature).
71–80 Character has amnesia (memories of intimates usually lost first; Knowledge skills useless).
81–85 Character has bouts of reactive psychosis(incoherence, delusions, aberrant behavior, and/or hallucinations).
86–90 Character loses ability to communicate via speec hor writing.
91–95 Character becomes catatonic (can stand but has no will or interest; may be led or forced into simple actions but takes no independent action).
96-100 THE VEIL IS SUNDERED + generate additional Insanity Effect.

If a character Sunders the Veil then a daemon has attempted to possess them.
This character must then must make will save versus DC10+1/2 daemons HD + daemons cha modifier trying to possess her (depending on the type of demon, this may be done in secret).

If passed the Arcanist maintains control of her mind, but should they cast another insanity generating spell (for as long as the insanity effect they normally would have generated lasts eg d10+4 rounds or d10 +4 hours) they must make the same will save with an additional negative -2 circumstance bonus each time they successively attempt this, as the daemon remains lurking to possess them.

If possessed, the rules for being possessed are per (page 22-24 of Fiendish Codex 1) and are suitably diabolical. However if the fiend has at least double the 1/2 HD + CHA Bonus of the Arcanist, in which case the following occurs;

The Arcanist is considered dead and no longer have control over their body - their body warps and within a round becomes that of the form of the daemon, though during that round the daemon may not do anything. The caster's animus remains locked in the body in torment until the daemon is banished. They may not be resurrected until this has been completed.

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