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Call of Cthulhu 7th Edition Cheat Sheet

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Citations and Abbreviations

Source Abbreviation
Call of Cthulhu 7th Edition Keeper Rulebook CoC 7E KR

Core Mechanics

Resolving Rolls and Checks

Rolls
Worst Bad Roll Good or Hard Roll Very Good or Hard Roll Extermely Good or Hard Roll Best Source
Roll Type Fumble Fail Regular Success Hard Success Extreme Success Critical CoC 7E KR

Pgs. 83 - 84, 89

Difficulty Definition - - Challenge a competent person. Challenge a profession. Challenge an Expert. - CoC 7E KR

Pgs. 82 -83

Dificulty Level - - Regular Difficulty Hard Difficulty Extreme Difficulty - CoC 7E KR

Pgs. 82 -83

Roll Value More than Skill or Score Less than Skill or Score Less than ½ Skill or Score Less than ⅕ Skill or Score 01 CoC 7E KR

Pg. 91

➀ If the skill is greater than 50%, a fumble occurs only on a roll of 100. Otherwise, a fumble occurs on a roll of 96-100.

Bonus and Penalty Dice

CoC 7E KR pg. 91

  • Bonus Die: Roll an extra tens die; take the lower result.
  • Penalty Die: Roll an extra tens die; take the higher result.

Opposed Rolls

CoC 7E KR pgs. 90 - 91

  • The highest level of success wins (Extreme > Hard > Regular > Fail).
  • Ties favor the defender.

Pushing the Roll

CoC 7E KR pgs. 84 - 85

Pushed Roll Basics

  • Allows a second attempt at a failed skill check if justified by extra effort or risk.
  • The Keeper asks, "What action are you taking to push the situation?"

Consequences of Failure

  • Failing a pushed roll results in severe consequences, such as:
    • Injury or breaking equipment.
    • Attracting unwanted attention.
    • Spending too much time, risking danger.
    • Obsessing over dark knowledge with mental consequences.

Rules & Limitations

  • Time always passes between the initial roll and the pushed roll.
  • The goal must still be achievable.
  • Skill difficulty usually remains the same but can change if the situation evolves.
  • Only skill and characteristic rolls can be pushed.
  • Luck, Sanity, combat rolls, and damage rolls cannot be pushed.

Special Rolls

Luck Roll

CoC 7E KR pg. 90

  • Luck rolls are called by the Keeper to determine external circumstances or fate.
  • If a skill or characteristic is relevant, it should be used instead of Luck.
Group Luck Rolls
  • When a Group Luck roll is required, the player with the lowest Luck score makes the roll.
  • If something bad happens to one investigator, the Keeper may assign it to the player with the lowest Luck score.
Spending Luck

CoC 7E KR pg 99

  • Luck points may be spent to adjust skill or characteristic rolls on a 1-for-1 basis.
  • Luck cannot be spent on:
    • Luck rolls.
    • Damage rolls.
    • Sanity rolls.
    • Rolls determining the amount of Sanity lost.
  • Players may only spend Luck on their own rolls.
  • If a roll fails, the player can either push the roll or spend Luck, but not both.
  • Luck cannot prevent criticals, fumbles, or firearm malfunctions.
  • No skill improvement check is earned for a roll modified by Luck.
Recovering Luck

CoC 7E KR pg. 99

  • At the end of each session, players may roll to improve their Luck:
    • Roll 1D100. If the result is above the current Luck score, gain 1D10 Luck points.
    • If the roll is equal to or below the current Luck score, no Luck is recovered.
  • An investigator’s Luck score may not exceed 99.
  • The starting Luck value is not used again and does not reset during play.

Know Roll

CoC 7E KR pg. 90

  • All people have general knowledge stored in their memory.
  • The Know roll represents an investigator’s chance to recall information based on their education (EDU).
  • To succeed, roll equal to or under the character’s EDU value.
Example
  • Knowing that pouring water into sulfuric acid is dangerous (without Chemistry skill).
  • Recalling the geography of Tibet (without a Navigate roll).
  • Knowing that arachnids have eight legs (even with only 1% in Biology).
  • Identifying present-day earthly languages.
Rules & Limitations
  • If a specific skill (e.g., Chemistry, Biology) is more appropriate, the Keeper may require that skill roll instead.
  • The Keeper decides when a Know roll is applicable.

Intelligence & Idea Rolls

CoC 7E KR pg. 90

Intelligence (INT) roll
  • An Intelligence (INT) roll is used when an investigator attempts to solve an intellectual puzzle.
    • Roll equal to or below the investigator’s INT to succeed.
    • Success provides a solution from the Keeper (e.g., solving a riddle or crossword puzzle).
Idea roll
  • An Idea roll is used when players are stuck in an investigation.
    • Made the same way as an Intelligence roll (rolling equal to or below INT).
    • Proposed by players when they have missed a vital clue or don’t know what to do next.
    • Success helps the investigators get back on track with minimal issues.
    • Failure may still reveal the clue, but at a cost or complication.
  • The Keeper determines when an Intelligence or Idea roll is appropriate.

Sanity

  • Sanity Check: Roll against current SAN.
  • Loss Examples:
    • Minor shock (1/1D4 SAN loss).
    • Horrifying event (1/1D10 SAN loss).
  • Bouts of Madness:
    • Immediate effects (e.g., fainting, fleeing).
    • Long-term effects determined by the Keeper.


Combat

Sequence

  1. Determine Order: Highest DEX goes first.
  2. Attack Options:
    1. Dodge: Avoid damage (no counterattack).
    2. Fight Back: Counterattack if successful.
    3. Maneuver: Inflict a specific effect (e.g., disarm).

Outnumbered Penalty

  • If a character dodges or fights back multiple times in a round, each successive roll incurs a penalty die.

Damage and Healing

  • Hit Points:
    • Major wound if damage >= half max HP.
    • Death if HP reaches zero and CON roll fails.
  • Healing:
    • First Aid: Restores 1D4 HP.
    • Medicine: Restores 1D4+1 HP.

Chases

  • Compare MOV values:
    • Higher MOV = Escape advantage.
  • Actions:
    • Move 3+ locations: Requires 1 action.
    • Hurdles: Roll appropriate skill to overcome.

Firearms

  • Base Ranges:
    • Regular range: No modifier.
    • Long range: +1 difficulty level.
  • Modifiers:
    • Point-blank: +1 bonus die.
    • Aiming for 1 round: +1 bonus die.
    • Moving target: +1 penalty die.

Reference Tables

Armor Values

  • Heavy Leather Jacket: 1 point.
  • Kevlar Vest: 5 points.
  • Military Body Armor: 12 points.

Insanity Effects

  1. Phobias: Character must avoid specific triggers.
  2. Manias: Character becomes obsessed with an idea or behavior.
  3. Delusions: Distorted perception of reality.

Damage Levels

  • Minor: Can survive without medical help.
  • Major: Requires immediate treatment.
  • Deadly: Fatal without intervention.

Quick Tips

  • Use skills creatively to overcome obstacles.
  • Keep an eye on SAN; long-term effects can derail plans.
  • Communication and roleplay add depth to investigations.

Character Creation

Determine Characteristics:

  • Roll 3D6 for STR, CON, POW, DEX, and APP.
  • Roll 2D6+6 for INT and SIZ.
  • Roll 3D6+3 for EDU.

Calculate Derived Stats:

  • Luck: Roll 3D6 x 5.
  • HP: (CON + SIZ) / 10.
  • Sanity: POW x 5.
  • Move: Adjusted by STR, DEX, and SIZ.

Choose Occupation:

  • Select a profession (e.g., Detective, Antiquarian).
  • Allocate skill points.

Choose Personal Interests:

  • Allocate additional points: INT x 2.

Flesh Out the Character:

  • Write a backstory.
  • Add connections, traits, and quirks.

Starting Equipment:

  • Based on occupation and Keeper guidance.