Foreword: I only just realized that without these rules the classes I am posting will seem incredibly impaired by the Psychological Disorder feature. That’s what I get for trying to post in page order *facepalm*.
3.0 Sanity & Psychological Disorders
NOTE 1 – All disorders can be found in D20 Call of Cthulhu Corebook pgs 52-56.
NOTE 2- Any Protagonist may wait to choose their Psychological Disorder until the conclusion of their first Tale (i.e. adventure). This is to give the player a chance to use that first horrific experience to scar the protagonist and in some ways can be easier for the player to explain and role-play.
NOTE 3 (VERY IMPORTANT!) – The disorders that Protagonists have are not a constant behavioral issue, they should only be brought into play on a failed SAN check. A player may choose to play up some of the quirks of his disorder but no one is required to play these disorders to the hilt except during those most horrifying of moments and the aftermath of such.
Whenever a Protagonist encounters a situation where he may lose SAN points he makes a D100 check against their current SAN, if he fails he loses the requisite number of SAN points (and may gain a number of Knowledge points depending on what caused the SAN loss). A 2nd check is then made against his new lower SAN score, if this check is failed then the Protagonist experiences an episode of his Psychological Disorder.
Whenever a Protagonist gains a level he adds 1d6 + WIS Modifier to his current SAN points. This increase can bring his SAN above his initial SAN score but never above his Max SAN score.
If, and when, a Protagonist’s SAN score reaches 0, he will have one of 3 permanent affects depending on his original psychological disorder: Permanent Catatonia (PTSD, Sleep Disorders, and Mood Disorders), Scared to Death (Phobias only), or a Permanent Psychotic Break (All other disorders).
PTSD (Post-Traumatic Stress Disorder) operates differently than in Call of Cthulhu. It is considered a separate disorder from the Anxiety Disorders due to it having a more direct external cause or singular event associated with its onset. If a character fails a SAN check after SAN loss then he immediately freezes up for the next 2 rounds (non-communicative and no actions but can be led by the hand). After that the Protagonist sinks into a Panic Attack (-4 to all Skill Checks and Combat rolls) for the next hour. Once that hour has elapsed the stress on his body will have exhausted him (-10’ to movement, -2 to all Skill checks and combat rolls) until he has a chance to sleep for 8 hours. Even after that he will be -1 to Skill Checks and combat rolls the next day due to fitful and nightmare-filled sleep. Once another 8 hours of sleep are taken all ill affects will abate. If a mild sedative is administered to the character then the penalties will be halved during the Panic Attack and Exhaustion phases.