CoC Rule Summaries and House Rules
Insanity and Addictions
Success is d100 roll =< Current Sanity.
- 5+ SAN loss to a single event requires Idea roll; success = Temp Insanity (i.e., failure means the memory is suppressed. Success means the memory is fully realized.)
- 20%+ SAN loss in one hour causes Indefinite Insanity for 1d6 months.
- Short vs. Longer Term insanity is determined by the current mental state and recent emotional strain (see section below for additional ideas).
- After recovery, a mild phobia or post-traumatic stress disorder may remain
Treatment of Insanity
- Psychoanalysis, Psychiatric medications, or Institutionalization: roll d100 per game month.
- 01-95: success, add 1d3 sanity points.
- 96-100: failure, lose 1d6 sanity points.
Short vs. Longer Temporary Insanity
This is not clearly defined. Here are a few suggestions from the web:
- If an investigator loses at least 1/5 sanity in an hour, they get a Long Term Temporary Insanity followed by Indefinite insanity.
- Sanity loss of 5+ points during combat and other “fast-paced” situations results in Short Term.
- Sanity loss of 5+ points during investigatory, study, or other “slow-paced” situations results in Long Term.
- Sanity loss of 5 is always Short. If Sanity loss is greater than 5, if less than or equal to 1/2 POW, Short; else, Longer.
Short Temporary Insanity (1d10 + 4 rounds)
On the first occurrence, gain +5% Cthulhu Mythos points. On subsequent occurrences, gain +1% Cthulhu Mythos points. Then, suffer one of the following affects:
01-10%: Fainting or screaming fit
11-20%: Flees in panic
21-30%:Physical hysterics or emotional outburst (laughing, crying, etc)
31-40%: Babbling, incoherent, rapid speech, or logorrhea (a torrent of coherent speech)
41-50%: Intense phobia, perhaps rooting investigator to the spot
51-60%: Homicidal or suicidal mania
61-70%: Hallucinations or delusions
71-80%: Echopraxia or echolalia (investigator does/says what others around him do/say)
81-90%: Strange or deviant eating desire (dirt, slime, cannibalism, etc)
91-100%: Stupor (assumes fetal position, oblivious to events) or catatonia (can stand but has no will or interest; may be led or forced to simple actions but takes no independent action)
Doubles: roll on the Longer Temporary Insanity to either replace or add to the Short Temporary Insanity, as seems most proper.
Longer Temporary Insanity (1d10 X 10 hours)
- Amnesia (memories of intimates usually lost first; languages and physical skills engaged, but intellectual skills absent) or stupor/catatonia
- Severe phobia (can flee, but sees object of obsession everywhere)
- Strange sexual desires (exhibitionism, nymphomania or satyriasis, teratopilia, etc)
- Fetish (investigator latches onto some object, type of object, or person as a safety blanket)
- Uncontrollable tics, tremors, or inability to communicate via speech or writing
- Psychosomatic blindness, deafness, or loss of the use of a limb or limbs
- Brief reactive psychosis (incoherence, delusions, aberrant behavior, and/or hallucinations)
- Temporary paranoia
- Compulsive rituals (washing hands constantly, praying, walking in a particular rhythm, never stepping on cracks, checking one’s gun constantly, etc)
Indefinite Insanity (1d6 months)
- Choose an appropriate insanity.
- Does not necessarily require treatment and removal from the game.
- May be continuous (e.g., amnesia, depression) or only manifest at particular moments (e.g., multiple personality, dissociative identity).
|Anxiety or severe phobia||varies, based on trauma|
|Dissociative||amnesia, multiple personality|
|Impulse control||compulsions: hand washing, praying, walking in rhythm, checking something constantly|
|Fetish||latches onto an object or person as a safety blanket|
|Personality||various neuroses, uncontrollable tics and tremors|
|Schizophrenia/psychotic||delusions, hallucinations, paranoia, catatonia|
|Sleep||night terrors, sleepwalking|
|Somatoform||psychosomatic conditions: blind, deaf, lost use of a limb|
|Substance abuse||alcoholic, drug addict|
|Megalomania||delusion about one’s own power or importance|
|Quixotism||extravagantly chivalrous or romantic, impulsive and rashly unpredictable|
- Each time a user takes a drug to which he is addicted,
- he is satiated and staves off withdrawal symptoms for the period of time indicated on the table
- he suffers a penalty to all skill and char rolls, as indicated on the table, for the next 24 hours
- An addicted user who is not satiated
- takes the indicated amount of ability damage each day unless the character succeeds on a Con Check against the drugs Addiction score
- If a character makes successful saving throws in a row equal to the Withdrawal Period, he has fought off his addiction and recovered, and takes no more damage from withdrawal symptoms
|Negligible||20||3-10||1d3-1 Dex (can be 0)||5-10%||2||Cannabis, LSD|
|Low||30||1-7||1d3 Dex or Con||10-20%||2-3||Alcohol, Valium|
|Medium||50||1-5||1d4 Dex or
Con + 1d4 Pow
|High||70||1-2||1d6 Dex +
1d6 Con +
|Extreme||n/a||1||1d8 Dex +
1d6 Con +
1d6 Str +
NOTE: reduction of any stat to 0 does not cause death, but does cause extreme debilitation and an uncontrollable, irrational desire to satiate.