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
| 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 | ➀ | 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
- Determine Order: Highest DEX goes first.
- Attack Options:
- Dodge: Avoid damage (no counterattack).
- Fight Back: Counterattack if successful.
- 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
- Phobias: Character must avoid specific triggers.
- Manias: Character becomes obsessed with an idea or behavior.
- 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.
