Now that you’ve had a chance to look at how Character Creation works in Call of Cthulhu, let’s start with the rules in the 7th Edition.
The Skill Roll
Call of Cthulhu is a game that relies mostly on percentile (d100) dice. Damage and some other effects are determined by other dice, but the pass-fail mechanic for most of the game relies on a simple percentile roll vs a difficulty set by the Skill of the Investigator.
While this is called a Skill Roll, this mechanic also applies for Characteristics rolls as well.
Determining the Difficulty of the Roll
Skill Rolls come in three types:
- Regular: Equal to, or below the Skill or Characteristic. This is the most common setting for majority of the rolls called for in the game.
- Hard: Equal to, or below half of the Skill or Characteristic. This task would challenge a professional, and should only be encountered occasionally.
- Extreme: Equal to, or below a fifth of the Skill or Characteristic. This would challenge even an expert, and should be a very rare and reserved for truly desperate situations
The Keeper determines the difficulty of the roll, and it’s important to remember if a task is easy, no roll is required.
Opposed Roll Difficulties
Should an Investigator find himself in opposed by someone else, then the difficulty of the roll is determined by the skill level of the opponent:
- If the opponent has a skill of below 50 or less, then the roll is made against a Regular Difficulty
- If the opponent has a skill equal to or above 50, then the roll is made against a Hard Difficulty.
- If the opponent has a skill equal to or above 90, then the roll is made against an Extreme Difficulty.
Call of Cthulhu prefers to take the stance where the players are the ones that roll. Keepers should frame checks from the point of view of the player. An example would be that the players roll Stealth if they’re sneaking up on an opponent, but roll Spot Hidden if the situation is reversed and someone is sneaking up on them.
Success, Failure and Pushing the Roll
In Call of Cthulhu, Skill Rolls basically has the standard Pass/Fail result, but we go one step further by allowing Investigators to re-try a failed test by Pushing the Roll. When Pushing the Roll, the Investigator invests extra time and effort in an attempt to defy failure and eke out victory from a bad situation.
The stakes get higher when pushing a roll, as the Keeper is actually mandated to foreshadow the consequences of failure, which is essentially a means by which the situation gets even worse than a standard failure.
In some situations, multiple characters can end up rolling. Either due to cooperation, or in order to all try to pass a test. The game provides a few helpful examples of both, and how the Keeper can rule as to what constitutes failure or success.
In cooperative tests, multiple players can roll, and if one of the Investigators succeeds, then the group is considered to have succeeded. However, in tests that involve all the players succeeding the test, such as individually making stealth rolls to try and go where they’re not supposed to as a group, then all the Investigators are discovered when one fails.
Critical Successes, and Fumbles
Rolling a 01 is a reason for celebration, and means that the Investigator making the roll achieves an improved success. Meanwhile, rolling a 96-100 is a Fumble for skill rolls with a difficulty of below 50, and rolling a 100 is a Fumble for skill rolls with a difficulty of 50 and above.
Luck, Know, Intelligence and Idea Rolls
In addition to the Skill Rolls, Call of Cthulhu is also equipped with a suite of key rolls that Players and Keepers can call on:
- Luck Rolls are called by the Keeper and are used to simulate the fickle nature of fate. Is there a crowbar nearby the unarmed Investigator that was ambushed by cultists? Call for a Luck Roll.
- Intelligence Rolls are called by the Keeper to determine if the Investigator can find the solution to a puzzle or or riddle.
- Idea Rolls are called for by the Players when they’re stymied in their investigation. This will help the players get the investigation back on track, rather than hitting a brick wall. Failing an Idea Roll doesn’t mean that the investigation stalls, but rather the cost of getting back on the trail will be more costly.
- Know Rolls are used to determine if an Investigator would be aware of a particular piece of trivia or information that they might have run into through their Education.
Overall, Call of Cthulhu isn’t a complicated rules system. Percentile systems have always been neat in the sense that even those who aren’t used to RPGs understand how good an Investigator is at a skill just by eyeballing the rating.
That said, there’s quite a few rules gimmicks (Luck rolls and the like) that exist in Call of Cthulhu’s system, and it helps for both the Keeper and the players to know what options they have available to them so they’re never unarmed.
I like that there’s a slant towards being able to keep an investigative trail alive despite failing a test. It keeps players from being too frustrated and doesn’t end a game purely on the basis of bad die rolling.
Next up, we’ll continue the rules as we look into Opposed Rolls and Combat!