pig-farm-controller/bmad/bmm/workflows/2-plan-workflows/gdd/README.md

Game Design Document (GDD) Workflow

This folder contains the GDD workflow for game projects, replacing the traditional PRD approach with game-specific documentation.

Overview

The GDD workflow creates a comprehensive Game Design Document that captures:

• Core gameplay mechanics and pillars
• Game type-specific elements (RPG systems, platformer movement, puzzle mechanics, etc.)
• Level design framework
• Art and audio direction
• Technical specifications (platform-agnostic)
• Development epics

Architecture

Universal Template

gdd-template.md contains sections common to ALL game types:

• Executive Summary
• Goals and Context
• Core Gameplay
• Win/Loss Conditions
• Progression and Balance
• Level Design Framework
• Art and Audio Direction
• Technical Specs
• Development Epics
• Success Metrics

Game-Type-Specific Injection

The template includes a {{GAME_TYPE_SPECIFIC_SECTIONS}} placeholder that gets replaced with game-type-specific content.

Game Types Registry

game-types.csv defines 24+ game types with:

• id: Unique identifier (e.g., action-platformer, rpg, roguelike)
• name: Human-readable name
• description: Brief description of the game type
• genre_tags: Searchable tags
• fragment_file: Path to type-specific template fragment

Game-Type Fragments

Located in game-types/ folder, these markdown files contain sections specific to each game type:

action-platformer.md:

• Movement System (jump mechanics, air control, special moves)
• Combat System (attack types, combos, enemy AI)
• Level Design Patterns (platforming challenges, combat arenas)
• Player Abilities and Unlocks

rpg.md:

• Character System (stats, classes, leveling)
• Inventory and Equipment
• Quest System
• World and Exploration
• NPC and Dialogue
• Combat System

puzzle.md:

• Core Puzzle Mechanics
• Puzzle Progression
• Level Structure
• Player Assistance
• Replayability

roguelike.md:

• Run Structure
• Procedural Generation
• Permadeath and Progression
• Item and Upgrade System
• Character Selection
• Difficulty Modifiers

...and 20+ more game types!

Workflow Flow

1. Router Detection (instructions-router.md):

   • Step 3 asks for project type
   • If "Game" selected → sets workflow_type = "gdd"
   • Skips standard level classification
   • Jumps to GDD-specific assessment

2. Game Type Selection (instructions-gdd.md Step 1):

   • Presents 9 common game types + "Other"
   • Maps selection to game-types.csv
   • Loads corresponding fragment file
   • Stores game_type for injection

3. Universal GDD Sections (Steps 2-5, 7-13):

   • Platform and target audience
   • Goals and context
   • Core gameplay (pillars, loop, win/loss)
   • Mechanics and controls
   • Progression and balance
   • Level design
   • Art and audio
   • Technical specs
   • Epics and metrics

4. Game-Type Injection (Step 6):

   • Loads fragment from game-types/{game_type}.md
   • For each {{placeholder}} in fragment, elicits details
   • Injects completed sections into {{GAME_TYPE_SPECIFIC_SECTIONS}}

5. Solutioning Handoff (Step 14):

   • Routes to 3-solutioning workflow
   • Platform/engine specifics handled by solutioning registry
   • Game-* entries in solutioning registry.csv provide engine-specific guidance

Platform vs. Game Type Separation

GDD (this workflow): Game-type specifics

• What makes an RPG an RPG (stats, quests, inventory)
• What makes a platformer a platformer (jump mechanics, level design)
• Genre-defining mechanics and systems

Solutioning (3-solutioning workflow): Platform/engine specifics

• Unity vs. Godot vs. Phaser vs. Unreal
• 2D vs. 3D rendering
• Physics engines
• Input systems
• Platform constraints (mobile, web, console)

This separation allows:

• Single universal GDD regardless of platform
• Platform decisions made during architecture phase
• Easy platform pivots without rewriting GDD

Output

GDD.md: Complete game design document with:

• All universal sections filled
• Game-type-specific sections injected
• Ready for solutioning handoff

Example Game Types

ID	Name	Key Sections
action-platformer	Action Platformer	Movement, Combat, Level Patterns, Abilities
rpg	RPG	Character System, Inventory, Quests, World, NPCs
puzzle	Puzzle	Puzzle Mechanics, Progression, Level Structure
roguelike	Roguelike	Run Structure, Procgen, Permadeath, Items
shooter	Shooter	Weapon Systems, Enemy AI, Arena Design
strategy	Strategy	Resources, Units, AI, Victory Conditions
metroidvania	Metroidvania	Interconnected World, Ability Gating, Exploration
visual-novel	Visual Novel	Branching Story, Dialogue Trees, Choices
tower-defense	Tower Defense	Waves, Tower Types, Placement, Economy
card-game	Card Game	Deck Building, Card Mechanics, Turn System

...and 14+ more!

Adding New Game Types

1. Add row to game-types.csv:

   new-type,New Type Name,"Description",tags,new-type.md
   

2. Create game-types/new-type.md:

   ## New Type Specific Elements
   
   ### System Name
   
   {{system_placeholder}}
   
   **Details:**
   
   - Element 1
   - Element 2
   

3. The workflow automatically uses it!

Integration with Solutioning

When a game project completes the GDD and moves to solutioning:

1. Solutioning workflow reads project_type == "game"
2. Loads GDD.md instead of PRD.md
3. Matches game platforms to solutioning registry.csv game-* entries
4. Provides engine-specific guidance (Unity, Godot, Phaser, etc.)
5. Generates architecture.md with platform decisions
6. Creates per-epic tech specs

Example solutioning registry entries:

• game-unity-2d: Unity 2D games
• game-godot-3d: Godot 3D games
• game-phaser: Phaser web games
• game-unreal-3d: Unreal Engine games
• game-custom-3d-rust: Custom Rust game engines

Philosophy

Game projects are fundamentally different from software products:

• Gameplay feel > feature lists
• Playtesting > user testing
• Game pillars > product goals
• Mechanics > requirements
• Fun > utility

The GDD workflow respects these differences while maintaining BMAD Method rigor.