🔍 The Momentum Matrix
Investigation design isn't about whether players find the clue. It's about what finding it costs them.
The Pixel-Hunt
The players are investigating a murder. There's a bloody handprint on the windowsill — it's the clue that points them to the killer's safehouse. One player rolls Investigation. They miss by two. The GM says: "You don't find anything useful."
The mystery grinds to a stop. The players know there's something to find — they're in the right room — but the dice declared it inaccessible. They either try again until someone rolls well enough, or they leave and miss the thread entirely. Neither outcome is good storytelling.
"A mystery that breaks on a bad roll was never really a mystery. It was a locked door that happened to look like a story."
"Clues are infrastructure, not rewards."
A core clue — the kind that moves the investigation forward from one scene to the next — is never locked behind a dice roll. It is always findable by active engagement alone. What the roll determines is not whether you find it, but how: the safety, the speed, the context, and what else you learn in the process.
A player who rolls badly still finds the bloody handprint. They just find it while the murderer's gang is coming through the door. The clue moves the mystery forward. The complication creates the tension.
Two Types of Clues
Core Clues
The forward-progress information. These are what the story needs to move from Node A to Node B. They are always findable by active engagement — no roll required to receive them.
The roll determines the conditions of acquisition: quietly or loudly, alone or observed, with extra context or without.
Contextual Clues
The texture, subtext, and depth. These enrich the picture — a motive behind the motive, a second layer to the villain's plan, a connection the players didn't know to look for.
A successful roll delivers these. A failed roll doesn't — but it never removes what was already guaranteed.
The Node Model
Scene StructureThink of each investigation scene as a Node — a location, encounter, or moment of discovery that contains clues pointing toward the next Node. Design each Node with three layers:
The Core Clue
What the Node must deliver regardless of rolls. This is the forward-progress beat — the bloody handprint, the name on the manifest, the map coordinate. Active engagement finds it. Period.
The Success Layer
What a good roll adds on top. A second connection. The villain's identity before the confrontation. The timing of the next move. Context that gives the players a real advantage going forward.
The Failure Cost
What a bad roll costs — always a complication, never the clue itself. They find the handprint, but now someone saw them find it. They read the manifest, but the page tears and takes part of it with it. Forward momentum maintained; tension increased.
Example Node — The Victim's Office
Core Clue: A name written in pencil on the underside of a desk drawer — the killer's alias. Always findable by searching the desk. Success Layer: A good roll also reveals a folded letter — partial, water-damaged — suggesting the victim was being blackmailed, not just killed. Failure Cost: They find the name — but knock over a glass in the process. The building's night watchman is now coming up the stairs.
The Momentum Rules
Design PrinciplesFour rules that keep any investigation running, regardless of how the dice fall.
Rule 1 — Never lock a forward clue behind a roll
If your investigation breaks when players miss a check, the design is the problem — not the dice. Every Node that needs to point forward must do so for any player who actively engages with it.
Rule 2 — A bad roll costs context or safety, not the clue
Failure introduces complication — noise, exposure, a watching eye, partial information, a ticking clock. It never removes the essential beat. The players take the next step; they just do it under worse conditions.
Rule 3 — Every Node has at least two paths in
If there's only one way to reach a scene, losing access to it kills the story. Design your mystery so each Node can be reached from at least two directions — two clues pointing at it, two contacts who know about it, two locations where the same information lives.
Rule 4 — The real investigation is interpretation, not discovery
Clues are most interesting when they require triangulation. Design scenes so multiple clues point at the same truth from different angles — the players aren't racing to find the answer, they're assembling a picture. The revelation lands when the picture becomes undeniable.
What Rolls Actually Decide
The ShiftIn a Momentum Matrix investigation, dice still matter — but they decide different things.
| Instead of deciding… | Rolls decide… |
|---|---|
| Whether the clue is found | How quietly and cleanly it's acquired |
| Whether the witness talks | Whether they require something in return, or become a liability |
| Whether the document is legible | How complete the information is and who else now knows you read it |
| Whether the player identifies the poison | Whether they also learn the antidote source — and how long they have |
| Whether the trail is followed | Whether they arrive before the scene has changed, or after |
Node Designer
Design a single investigation scene. When you're done, copy the result to your session notes.
What this scene must hand over, regardless of rolls. The forward-progress beat.
Contextual clues, extra depth, a strategic advantage. Not required to move forward — but valuable.
Complication, exposure, danger — they still get the Core Clue, but now something is worse.
Investigation Node
Connected tools in Story Craft: