Call of Cthulhu 7th Edition

How to play Call of Cthulhu 7th Edition

A fast, practical overview. Call of Cthulhu 7th Edition is a horror investigation roleplaying game based on H.P. Lovecraft's Cthulhu Mythos. Players take on the roles of Investigators, ordinary people who uncover cosmic horrors beyond human comprehension. As you investigate mysteries, your character's Sanity slowly erodes, skills improve through use, and the line between reality and madness blurs.

Beginner checklist

Describe what you try to do (then pick the most relevant skill).

Roll d100 and try to roll under your skill.

Use difficulty bands (Regular/Hard/Extreme) to set stakes.

Track Sanity and consequences; failing forward is normal in investigation play.

How rolls work

Call of Cthulhu uses percentile skills: roll d100 and succeed if you roll at or under your skill. Difficulty often shifts the threshold (Regular/Hard/Extreme) and Sanity loss is a core pressure loop.

Pick the relevant skill (e.g., Spot Hidden, Library Use).

Roll d100 and compare to your skill rating (and difficulty threshold).

Apply consequences: information gained, complications, or Sanity loss when appropriate.

Example

Spot Hidden 55%: a roll of 42 succeeds; a harder threshold would require a lower roll.

Key facts

Percentile skill system: Roll d100, succeed if equal to or below skill rating

8 Characteristics: STR, CON, POW, DEX, APP, SIZ, INT, EDU (plus Luck)

Occupation system: Each occupation grants skill bonuses and Credit Rating range

Sanity mechanics: Starts at POW, maximum reduced by Cthulhu Mythos exposure

Skill improvement: Mark skills during play, improve after sessions

Luck: Spend after a roll, point for point, to turn a failure into a success; can't be used on Sanity, damage, Luck rolls, or pushed rolls

Derived stats: HP, MP, Sanity, Build, MoveRate, DamageBonus

Play examples

Spot Hidden under pressure

You search a room fast before the cult returns. Roll Spot Hidden; a Regular success finds the clue, a failure still finds something but costs time or adds a complication.

Hard/Extreme as stakes

If the clue is tiny or conditions are bad, the Keeper can call for Hard/Extreme. You're not changing the scene, just raising the required quality of success.