claude-config/skills/rpg/references/convention-one-shot.md

Convention One-Shot Structure

The house format for 4-hour convention slots. This structure is proven across Continuum, Contingency, ChaosiumCon and Airecon games — deviate only with a stated reason in the Design intent.

Master Rules

Structure

• Introduction → Act One → Act Two → Act Three → Epilogue
• Maximum runtime 3h30 (210 min) of play inside a 4-hour slot, plus a 10-minute break — ~3h40 wall clock, leaving real margin: strangers at a con table run slower than any playtest.
• Budgets: Intro 15 · Act One 60 · Act Two 90 · Act Three 30 · Epilogue 15. These are ceilings, not fills — plan ~3:15 of actual content against them. A scenario that playtests "on schedule with zero slack" is over-stuffed.
• The session clock counts play time. Pause it during the break; every cumulative time and checkpoint in the scenario is on that clock. (The GM console's clock supports this.)
• Act Three always happens. Compress Act Two if needed; never sacrifice the climax. Hard rule: at 2:45 on the clock, go to Act Three regardless.
• Every act ends with a Pacing Note: what must be true before the next act, and a specific fast-track action if the clock has beaten the table.
• Place the 10-minute break at the end of Act One, on a natural cliffhanger.
• A one-shot must end written: closure or designed ambiguity, never an unwritten "to be continued". The Epilogue includes an outcomes table (Full / Partial / Failure / Pyrrhic — or scenario-specific named endings) and an adaptable closing read-aloud.

Timing table

Include a Session Timing Guide with a GM Checkpoint column — a one-line test the GM can apply mid-session ("both copies met, chase done, deadline known"). Checkpoints are what make the timing table usable in play.

Clues — the house standard

Every essential clue has three routes to the players:

1. Automatic on the right approach — the right skill or question in the right scene finds it without a roll; rolls only buy extra information.
2. A written fallback — NPC volunteers it, environmental prompt, second location.
3. The Countdown — a proactive antagonist move that delivers or forces the revelation (this is the universal third route; it's why the Countdown table is mandatory).

Plus:

• Clues form a guided trail — each points to the next, but players should feel they discovered it, not followed a map.
• Every act: at least one essential clue and one optional clue (optional = reward for thorough play; trail survives without it).
• Essential clues never live behind a search roll or in a location's "Hidden" line — Hidden is for optional/extra material only.
• Clue trail is a table per act: # | Clue | Location/Source | How Found | What It Reveals | Type. Number clues continuously across acts, one fallback line per essential clue.
• Keep a Revelations checklist (8–12 one-liners, abstracted from where they're found) after the Plot Summary. Anything undelivered by the end of Act Two is folded into Act Three's confirmation scene or consciously dropped — the Act Two Pacing Note says which. Beyond that, Act Three contains no new information — only confirmation and consequence.

The countdown clock

Antagonists and world events move on schedule whether or not players act. Write a timetable ("The Countdown") the GM advances when the party stalls — and make each advance felt (a glimpsed van, a witness gone quiet). Keep the opposition one step behind the players until the climax — pressure, not punishment.

Design intent block

Right after the Overview, 3–5 numbered statements, e.g. "Investigation-first: no required combat", "Built to split: Acts One and Two run as 2+2 parallel tracks", "Ambiguous ending: conversation, not firefight". This is the contract the rest of the document must honour, and the first thing a reviewer checks.

Plot Summary + Player Experience

Two views of the same scenario, both mandatory:

• Plot Summary (GM truth) — what actually happened/is happening, player-independent, with a dated timeline. Players never see this page.
• Player Experience — one paragraph of the scenario as lived from the table, second person, spoiler-shaped but honest. This is the pitch — if it reads flat, the scenario is flat.

Slot logistics

• Default 4 players with pregens (6 max for some systems — pick per game and say so). The Overview states the scaling line: which player counts the scenario runs at, which pregen drops first at fewer, how splits adjust. Nothing essential may live only on one PC.
• Safety tools, stated in 30 seconds, no ceremony (X-card or open door — UK cons expect it, and scenarios with private seams that cut close need the exit ramp). One line in the Introduction covers it.
• Slot Zero (the first 15 minutes, before the fiction): seating + safety line → pitch each pregen in one spoken tagline (the sheet's italic essence line) → players choose or GM deals in ≤5 minutes → open in motion.
• Party splits are a feature: parallel scene tracks (Track A / Track B) with engineered cross-team payoffs — each half holds half of a revelation. Alternate between tables in ~12-minute segments, ending each segment on a pull ("what was the hurry?").
• One set-piece per scenario (chase, heist, séance...) with its own GM quick-reference page. During set-pieces, give idle players jobs: hand them the obstacle cards, let them voice the bystanders.
• Content warnings in the Overview. Conventions require them and players deserve them.

Endings

• Aim the climax at a decision, not a die roll. The best Act Three is a situation where every choice costs something and the scenario honours all of them ("nobody gets to be right; the players decide who pays").
• Write an "If someone shoots" (or equivalent chaos) contingency — the table that torches the negotiation must also get a real ending.
• List compromise endings players will invent (partial trades, third options). If a playtest finds one, write it in.
• Epilogue delivers per-PC vignettes keyed to the outcome, then table debrief. Land the last line on the scenario's theme.
• Early finish (table cracks it at 2:30): expand the per-PC vignettes, then run The Tangent as a bonus scene — it's already written.

Fitting the slot (cut discipline)

• Plan ~3:15 of content against the 3:30 budget; playtest timing includes setup drift.
• Pre-write the cuts: each act's Pacing Note names what to drop first.
• Deploy pressure lines (an NPC checking a watch) at the first sign of circular table debate, not when the clock is already lost.