Role-playing games can be played without reference to the rules. People have character sheets. The game master has a rough idea of a situation. And things just coast along somehow with the the numbers on the character sheets being used however the mood strikes him. If combat is not engaged, little more than a tithe of the actual rules will be invoked.

Call of Cthulhu can be played that way. But it’s not actually intended to be played that way. There are things engineered into the rules that are designed to produce a type of play that is fairly well at odds with the sort of game that game masters would tend to improvise.

Here are several just from this chapter alone:

• For skill rolls that emerge in conflicts with living beings, the difficulty level will be a function of the opponent’s most relevant complementary skill.
• The breaking up of the “non-success” and failure results into separate rolls mean that disaster is only going to happen when the players intentionally push their luck.
• The foreshadowing of what the failure result would be that the Keeper does before a player commits to a pushed roll is an absolutely essential design element. If you’re not doing this, you’re playing it wrong!
• There are no saving rolls in this game. There is far less combat. Players tend to split up a lot. The “certain death” outcomes deriving from pushed skill rolls can (in order to fit with the source material) result in a Weird Tales style reframe.
• Astonishingly, opposed skill rolls are meant primarily for when players are in conflict with each other. Countless hours of classic D&D play is going to drive this out of people’s capacity to even think of doing this. (Nobody I’ve seen playing or talking about playing Call of Cthulhu plays this way.)
• The bonus and penalty dice are intended for… opposed skill rolls. Which are intended to be in player versus player situations. People coming from, say, 5th edition D&D will tend to use them for practically anything else.
• Everybody seems to know that you improve in skills that you successfully use in a session, but Sanity and Luck can recover or improve as well. When people assume that long-running campaigns are impossible with Call of Cthulhu, it’s because they aren’t aware of this.
• The money and credit rating rules allow people to play freely without keeping up with a tedious inventory. But unlike, say, GURPS… a player’s overall wealth level is expected to change from session to session. (Particularly when characters miss work or go insane, etc.)
• Players never have enough information and are always keen to get more. The suggestions on how to handle failure with regards to establishing contacts is another obvious application of both the rules and the source material that will not necessarily be obvious to people coming in from other games.

This game is different. Scenarios that are developed to leverage these rules are going to be different, too.

And yes, people will have plenty of fun hunting for clues while they wait for their Keeper spring the awesome finale sequence on them. But I think play will develop along different lines if the sort of situations these rules are pointing to are incorporated what happens at the table.

Are the adventure modules designed for the game built to leverage these rules and encourage their application? Or are they meant to perpetuate an unofficial pidgin variant of the game? If the latter is the case, then it wouldn’t be the first time that happened in gaming.