Shadowdark to Cairn: A shift from "Rules First" to "Rules Trailing"

I've got some miles on my Shadowdark book. At the time of this writing, I've easily run a fairly absurd 300+ sessions. Which is to say, I'm pretty familiar with that system.  

Recently, I ran Cairn and found... well... Not what I expected at all. Oh, I had heard of it, but I'm an OSR guy, and I don't run "story games," I run dark survival horror the way my first DM did in 2e when I was a teenager. Which is to say, I was uninformed.

What I found when I dug in has changed how I run games, even in Shadowdark, and I wanted to put some of that down here for the benefit of the wider community.

The Game Interface

Rules First

Typically, a player will interact with a TTRPG at the table through the rules system. I don't mean theater of the mind vs. maps and minis, or VTT vs. meatspace. I mean, they announce some type of Action, be it a move, an attack, or some sort of skill, the GM Adjudicates an outcome, and the Fiction state is updated as a result. We don't really think about it, because every game works this way.

Player Intent -> Rules -> GM -> Fiction

Players look at the challenge in front of them and select the sharpest tool, be it a class feature, a feat, or something else. Occasionally, you get a new player who has no frame for TTRPGs, and for a while, they will do really imaginative stuff. But eventually, they learn the rules and optimize for the outcome.

I've run some other narrative-focused systems, and mostly didn't love them. They all seem to abstract the procedural parts of the game that I enjoy, and the fiction is either left in a total free-for-all or it's run by Playbooks/Moves. But even those games follow this "Rules First" interface structure.

Rules Trailing

Cairn does not follow this pattern. In Cairn, the player directly updates the Fiction, and the DM responds to it using this subsystem framework. I hesitate to use the term "Rules" there because, in Cairn, any rule is a contextual manifestation of a subsystem.

Player Intent -> Fiction

GM -> System -> Fiction

Let's look at that in practice.

The player has a clue from another room that there is a secret door somewhere along this wall, so they light their pipe and gently blow smoke along the nooks and crannies. They've taken an Action and directly updated the Fiction. They don't need permission from the GM or the system. That is now the new state of the room.

The GM knows there is a secret door there, and that the method the player used to find it would obviously succeed. This takes a turn to complete, which means there is an event roll, which results in some form of loss. The GM tells them that they have found a space on the wall where the smoke is sucked in through some cracks. This seems to have activated the door latch mechanism, and as it slides open, the air pressure between the two rooms equalizes, blowing out the torch. The GM has now used the system to update the fiction in response to the player's Action.

Is that really all that different?

Notice that the player never "pressed a button on their sheet," and they didn't use any skill to locate a door. They acted directly upon the fiction, and the game responded. It was still procedural, but there was little mechanical interaction for the player to optimize a build around. They had to take the location at face value and just act naturally within it.  

And we didn't trade that freedom of player intent for a playbook that rewrote the fiction on the fly. The GM was still completely free to adjudicate what would reasonably happen in that situation. We ruled that this would work and that an event roll would inform the nature of the cost.  

We're getting the best of both worlds with this. And we're spending more of the session in the sweet spot of the game loop, instead of "mother-may-I-with-dice"