/game-brainstorm

name: game-brainstorm
description: >
  Runs designer-led ideation that turns a mood, theme, genre or "something like X" into three
  original concepts and one chosen Game Concept Document with core loop, pillars, player fit and
  scope, plus 5-10 minute web or jam hooks. Use for "game idea", "brainstorm", "pitch", "what should
  I make", "a game like X". Not for market sizing (use game-market-research).
argument-hint: "[theme, genre, 'like <game>', 'web hook', or 'open']"
effort: medium
allowed-tools: Read, Glob, Grep, Write, AskUserQuestion

AlterLab GameForge -- Structured Ideation Workflow

Most game ideas die from lack of structure, not lack of creativity. A notebook of "what if" lines never becomes a game without deliberate shaping. This workflow takes raw interest through seven phases that alternate between divergent thinking (expand) and convergent thinking (decide), and ends with an original concept a team, or a team of one plus coding agents, can build.

It is a conversation, not a form. Claude brings structure, provocations and options; the designer makes every decision. Early phases have no wrong answers. By the end, every answer has survived player psychology, a quick reality check, and honest scope.

**Continuity through files.** Read `.gameforge/project.json` (engine, phase, existing pillars), anything in `design/`, and `production/session-state/active.md` before starting. Write the result to `design/concept.md` (or `design/concepts/<slug>.md` when comparing several) and update `active.md` with the decision and the next step.

When NOT to use me

| The user wants... | Route to | |---|---| | Market size, comparable titles, positioning with real data | `/gameforge:game-market-research` | | Feedback on a design document that already exists | `/gameforge:game-design-review` | | A full GDD written section by section | `/gameforge:game-gdd-author` | | To test whether a mechanic is fun | `/gameforge:game-prototype` | | A jam: theme just dropped, clock running | `/gameforge:game-jam-mode` (its 20-minute theme step replaces this skill) | | To build the chosen hook tonight with an agent | `/gameforge:game-vibe-code` | | Vision and pillars for a game already in production | `/gameforge:game-creative-director` |

Choose a mode

Ask with one AskUserQuestion at the start (skip if the argument makes it obvious):

| Mode | When | Time | Output | |---|---|---|---| | **Full concept session** (default for commercial projects) | Starting a real project | 1-3 hours, can span sessions | Game Concept Document | | **Fast lane: web hook** | Weekend, portal or AI-friendly jam game; "playable tonight" | 20-40 minutes | Three concept cards, one chosen, handed to `/gameforge:game-vibe-code` | | **"A game like X"** | The user names an existing game | +10 minutes | Originality protocol first, then either mode | | **Genre pack variant** | Roguelike/roguelite or narrative-driven game | Adds to either mode | Genre-specific prompts layered on Phases 1-4 |

Critical Rules

1. **The designer decides.** Offer options, frameworks and provocations; never hand over a finished concept as if it were theirs. Even in the fast lane, present three and let them choose. 2. **Emotions before features.** "What should the player feel?" comes before "what do they press?" 3. **Constraints are fuel.** Team, time, budget, platform and skills shape the concept from minute one, not at the end. 4. **The 30-second loop must be fun naked.** Strip progression, story and unlocks; if the moment-to- moment loop is not engaging on its own, no content will save it. 5. **No precious ideas.** A concept that fails a later phase is discarded or reshaped. Kill concepts here, not six months into development. 6. **Original IP only.** Genre mechanics are free to use; another game's names, characters, art, music, levels, story and recognizable look are not. "Clone X" becomes an original design that keeps the mechanic the user loves (see the Originality Guardrail below). 7. **Honest scope.** Twenty enemy types with one part-time artist is a finding, not a detail. 8. **Use the shared theory.** MDA, Self-Determination Theory, Bartle types and Flow are defined in `${CLAUDE_PLUGIN_ROOT}/docs/game-design-theory.md`. Point there; do not reinvent definitions.

Step 0: Context and constraints

Read the project files listed above. Then capture constraints in one AskUserQuestion round (offer defaults; skip what `project.json` already answers):

| Constraint | Options | |---|---| | Team | Solo / 2-5 / 6+ (and whether coding agents do most of the implementation) | | Time | Jam or weekend / 1-3 months / 3-12 months / 12+ months | | Platform | Web / PC (Steam) / console / mobile / several | | Art and audio capacity | Programmer art / own skills / asset packs / dedicated artist / AI-generated with provenance |

The seven phases

Full prompts and fill-in templates for every exercise are in `${CLAUDE_SKILL_DIR}/references/ideation-exercises.md`. Read the relevant section before running a phase; below is the purpose, the deliverable and the judgment calls.

Phase 1: Creative discovery (diverge)

*Goal: find what genuinely excites the designer before touching mechanics.*

• **Excitement inventory:** the game that made them lose track of time, a moment they still think

about, the emotion they most want to create, a non-game experience worth translating.

• **Reference mining** across games, film, books, music and real life. Unexpected connections (the

pacing of a film with the system logic of a real job) beat "X but with guns."

• **Constraint inventory** (from Step 0).
• **Anti-inspiration:** what they are tired of, mechanics they find tedious, what they refuse to make.

Deliverable: three to five recurring themes and one target emotion. Ask, listen, reflect the themes back; do not rush to concepts.

Phase 2: Concept generation (diverge)

*Goal: three to five distinct concepts from at least two different techniqu