Heroes and Ordinaries

There are 3 types of characters in Down Cthulhu:

Ordinaries are as in the core. Upon failing a sanity check, ordinaries must make a DC20 will save or suffer an immediate effect. These may be temporary or permanent.

Heroes are as in the core except they get Personal Firearms Proficiency for free.

Super Heroes represent a majority of PC’s, and select NPC’s (including possible Super Villains). Supers get Personal Firearms Proficiency as well, plus the feat progression, extra talents, and ability scores generation detailed below. They also receive 3 hero cards at the beginning of each session. Unused cards may be carried over to the next session, at which point the character will receive enough new cards to total 3.
Regular heroes still roll 4d6 six times and arrange as desired or use an array determined by the DM. Ordinaries use an array as in the core.

All characters, upon losing sanity equal to their wisdom score in a day, suffer an ill effect.

Super Heroes

Creating ability scores:
The average array for super hero/villain is 18, 16, 14, 14, 12, 12.

Roll 3d6 for all stats, leaving them in the order rolled . Then, roll 8d6. These are your discretionary points. You assign these as you see fit on a one for one basis until a stat reaches 15. It costs 2pts to take it to16, 2 to take it to 17, and 3 points to take it to 18. 18 is the maximum before other modifiers.

Gain an ability score raise every even level, rather than every level divisible by 4.

1 extra skill point per level.

3 feats at first level and 1 feat every level thereafter rather than the standard feat progression.

1 bonus talent at every odd level, which can be chosen from any base classes you have at least 1 level in.

Gray Eyes

Some extraordinary characters are ‘Gray Eyed’. These characters gain a plus 2 to any single ability score (this may take a stat above 18), as well as a plus 1 to all saving throws. They also gain additional special abilities unique to each individual Gray Eye. See The Grey Eyes wiki page.

Making up levels

All PC’s begin at 0 XP, though they all begin above first level. While the teams are making up their experience through their previous levels, each PC may gain one thing from what will be gained at their next level, from list below, upon reaching 2nd, 4th and 6th levels, but only up to their starting level. At that point, at which they are truly gaining new xp, they may gain abilities at 3 ‘sublevels’ before reaching a new level. This all is to give a sense of accomplishment, considering the greatly slowed rate of levelling up in Down Cthulhu.

  • Base Bonuses (Base attack, save and defense bonuses)
  • Fatigue Points
  • Class Features: this includes talents, bonus feats and advanced class abilities
  • A Character Talent, those given by the GM as a bonus.
  • A Character Feat: that which PC’s get at every level.
  • Skill Points, including language points if any
  • Sanity and Power
  • Profession check for Wealth increase, and reputation increase if any
  • Effective level/HD to determine special effects, like vs SR or if an spell is powerful enough to effect you, or the effectiveness of your own abilies with variables based on your level.
  • Ability Score raise, if going up to an appropriate level

So, for instance, the Outlaws are 6th level. When their XP total passes 2nd, they may pick one of the above categories for whatever class they will go up in at 7th level, accept for ability score raise. The Aether Travellers on the other hand, being 3rd level to start, could choose ability raise.
Obviously, for many choices, you must know what class you will be taking for your next level.


Gaining languages works very differently in Down Cthulhu, including a linguist feat and a linguistics skill.
First, languages require skill points in them to learn to certain degrees. A character can not have ranks in more languages than his intelligence modifier + 1(not counting his native tongue). If a character puts ranks into either or both of the linguistics skills (see below) he can have ranks in a number of additional languages in that category of languages equal to his linguistics ranks.
At first level, you receive free language pts equal to your intelligence modifer + 2 for which to purchase language ranks only. If you have a positive intelligence modifier, you receive one free language skill point each level thereafter. You also gain 1 language point for each rank in one of the 2 linguistics skills you have, but they may be spent only in the appropriate languages. Language points may be saved up over time. You may also spend your normal skill points on languages.

1 rank = simple communication is possible, but complex plans and academics impossible. This rank requires a DC 10 linguistics check an 2 weeks exposure.
2 ranks = Speak fairly fluently but with an obvious non-native accent. DC 15 and +1 month of concentrated exposure to gain this rank. This is the typical level for someone who knows a language well or needs it academically.
3 ranks = Flawless speaker, knows idioms and nuances well, as good as a native. DC 20 and + 2 months concentrated exposure to earn this rank. This is the assumed number of ranks one has in their native tongue.
4 ranks = a true expert with a linguist’s knowledge of the grammar and syntax and you may even be able to pass yourself off as a native with a linguistics check. DC 25 and + 2 years concentrated exposure to earn this rank. You know it so well you may gain small bonuses to charisma based checks and writing checks. If you are teaching someone the language they gain a +2 to their linguistics check to earn a rank. Some of the best writers have this level in their native tongue.
+1 rank: to read and write a language you must have at least 2 ranks in. Typically, a character has this rank in his native tongue for free.
Ancient languages work similarly to above, but are condensed into 3 ranks and you do not need the extra rank to read and write, as that is how one learns them to begin with. However, with a 3th rank, you may be able to communicate in the dead language with a linguistics check. You may only be able to receive and transmit the amount one would pick up with a deciper script check for written languages. With a 4th rank you may freely communicate with that dead language as if you had learned it as a living language.
exposure typically means intensive study every day or immersion by way of living amongst native speakers and making an attempt to learn the language each day.

modern linguistics (int): you put ranks in this like any other skill. For each rank (including trained bonus), you may have ranks in one additional language beyond the normal limit, and you gain 1 language point to spend on appropriate languages. To put a rank into a language you must make the appropriate linguistics check. For each previous failure, until success, you gain a cumulative +2 on your next attempt.
ancient linguistics: works like Linguistics above, but for dead languages.

linguist (req.: int. 13 or higher;first level only) : you gain a +2 to linguistics checks. You receive 4 bonus language skill points/level.

Hit Points

Hit points are split between fatigue (the hp you role based on class + con. mod) and wound points (= to your constitution score).
You also have a heroic reserve = to your fp. From this reserve you can heal fatigue quickly on a one for one basis. Non-lethal points heal at twice that rate, as well as one free non-lethal for every lethal fatigue healed.
Wound Points get divided into thirds, with unequal portion added in the first. The first third constitutes only light wounds and have no adverse effect. The second third are moderate wounds and give a -2 penalty to strength and dexterity. The last third are serious wounds and cause an additional -4 to str and dex. These penalties are gone as soon as the points are healed.
Wound points come back slower, on a /day basis. The maximum you can heal in one day is 2 + your con. modifier. It is a fortitude save, base DC 10 for light damage, DC15 for moderate, and DC20 for serious. Add your amount of wound points to the base DC. You heal 1 point + 1 per 5 you beat the DC. Each day you fail you receive a cumulative +1 to the check the next day. This save can be modified by extended rest and/or a Treat Injury check for long term care. Full day of bedrest adds +4 to the heal check, 8 hours rest adds 2. A doctor’s kit adds a +2 and a hospital a +4 to the doctor’s roll.
Once/day on a given character, and only once for a give wound, the Treat Injury skill can heal wound points instantly. DC 15 heals 1pt + 1 additional/5 points your roll beats 15.


Gunbelts hold 20 rounds
Bandoleers hold 45 rounds
4 3/4" revolvers gain a +1 to intitiative on a fast draw.
Single Action revolvers adds a +1 initiative to a proficient user on a fast draw for the round they are drawn due to the cocking of the hammer while drawing. The gunman must have quick draw and a +1 BAB


Defensive Roll (Fast Hero): The save is 10 plus the amount the enemy beat your defense.


Brawl:: does not provoke an AoO. Otherwise unchanged. Nonlethal damage works like in dungeons and dragons, aka subdual damage.
Combat Martial Arts: due to the modification of Brawl and the use of fatigue points creating less of a difference between lethal and non-lethal damage much of the time, this feat does not modify the die rolled, but instead grants a plus 2 to damage with unarmed attacks. Otherwise unchanged.
Adaptive Personality: this modifies diplomacy not knowledge checks.
Weapon Specialization: This feat is added back into the list of available feats, with a requirement of BAB +3 and Weapon Focus in the same weapon.


The Pathfinder class skill system is in use in place of the core.
Cryptography is an added skill.
Drive and Pilot are broken down differently.
Move Silently and Hide are folded into Stealth.
Diplomacy and Gather Information are folded into Persuasion.
Listen and Spot are folded into Perception, which includes all the senses. Each character chooses one favored sense and one poor sense. With the former they gain advantage, with the latter they gain disadvantage.
Balance and Tumble are folded into Acrobatics.
Knowledge skills: for each skill point you put in a field that has subskills, you gain 2 ranks to distribute among subskills.
Wilderness has subskills based on climate/terrain type and is purchased like a knowledge skill with subskills.
There is now a separate Knowledge (archaeology) skill. You may spend ? skill points to choose a specialty field within either with which you gain advantage. You may buy a maximum of 2 in each of these knowledge skills.
Decipher Script is gone, it now falls under linguistics, modern; linguistics, ancient; cryptography.

Forbidden Tomes and Lore

All die types for randomly determined study times to read forbidden tomes are cut in half. So, a book that in Call of Cthulhu takes 2d8 plus 1 week instead takes 2d4 plus 1 weeks.

Invention Rules

Every invention falls into 1 of 50 types. 10 fields of study, each with 5 levels.
It takes 20 research points/level to finish researching an invention.
Inventors gain 1 die in each research area per rank (incl. the trained bonus). So whenever you gain a rank via skill points, you gain an invention die. You can spend these to add ranks to disciplines.

Every 5 points in a Field of Study is knowing it at level 1,2,3…

Spending time studying a FoS can give you ranks as well, which are specific to that FoS, not
Every level, you get bonus research dice equal to your wisdom mod that you keep separate to spend as you please. This symbolizes the ‘Yurika!’ moment. (I think perhaps this should cost a feat)

Rather than a bonus equal to your int. mod./die, perhaps:

  • For each feat or the like you have giving a +2 to a relevant science, add 1 to each die, or perhaps just a free extra d6.
  • For every +3 from skill emphasis or savant, you gain a research die.
  • Use Advantage from DND next? ex. for your int. mod. of rolls, roll 2d6 and take the highest.
  • For every bonus you have, you may gain advantage on a experimental role, or add a chosen bonus to it, or gain advantage on a number of research dice equal to you intel mod for each point used.


First 10 feat as normal. Jump and Tumble eliminate next 10 as normal. After that, first 10’ is 1d6, then 2 more, then 3 more, then 4 more, then 5 …..
Falling is subject to Threshold.


Canal Martians: plus 2 dex and cha; minus 2 str and con
Hill Martians: minus 2 str; plus 2 dex
Selenites: plus 2 str, con; minus 2 int; minus 4 cha
Venusian Lizardfolk: as d20 lizard man


Down Cthulhu, The Occult Wars ruleslawyermark