GDD: PROJECTILE WAR

PROJECTILE WAR

Complete Game Design Document (Overview)

3 Cannons • 2 Shields • 8 General Maintenance
Version: 2.0 Final (2025-11-02) • Status: Production Ready
Designer: Guillermo Ithier • Validation: Verified through multiple simulations; classroom playtested in a high-school physics classroom (block schedule).

Submission Scope: This document is a design overview; full card list, numeric tuning, and the complete ruleset are available on request.

Copyright & Submission Notice

© 2025–2026 Guillermo Ithier. All rights reserved.
PORTFOLIO COPY—EVALUATION ONLY.
No license is granted. No copying, distribution, adaptation, or forwarding without the express written permission of the copyright owner.
Document ID: PW-GDD-v2.0-2025-11-02

Version Control

v2.0 Final • 2025-11-02 • Production Ready • Designer: Guillermo Ithier
Verification: Verified through multiple simulations; classroom playtested.

Table of Contents

1. Title and Core Concept
2. 1.1 Design Differentiators
3. Design Pillars
4. Components
5. Setup
6. Core Mechanics Overview
7. Prototype Testing and Classroom Playtest

1. Title and Core Concept

Title

PROJECTILE WAR

Tagline

“Command your artillery. Manage the chaos.”

Genre

Tactical, card-based artillery duel

Players

2 players (competitive head-to-head)

Duration

10–12 minutes per game

Age Rating

12+ (strategic complexity and arithmetic)

Complexity

Medium (easy to learn, difficult to master)

Core Concept

Two commanders engage in a tactical artillery duel. Each player controls three cannons protected by two shields. Firing generates mechanical Stress (σ) on the active cannon: push too hard and your cannon detonates; play too cautiously and you lose tempo. Victory comes from rotating cannon usage, timing Maintenance, and breaking enemy shields efficiently.

1.1 Design Differentiators

• Three-cannon Stress tracking: Each cannon accumulates σ independently, forcing rotation decisions and deliberate “overheat windows.”
• Unified dual-purpose Maintenance: One Maintenance card stabilizes cannons or supports shields, creating a clean tempo-versus-survivability trade.
• Readable risk curve (2d6 + Stress escalation): 2d6 keeps outcomes learnable while σ-driven escalation makes “push vs reset” decisions meaningful.
• Fast, low-downtime cadence: One action per turn with hand refill to 5 sustains pressure and supports 10–12 minute matches.
• Entropy-driven endgame: Accumulating degradation (σ/Φ) prevents stall patterns and forces decisive play.

2. Design Pillars

2.1 Meaningful Tension

Every action is a tradeoff: offense creates pressure but increases Stress; Maintenance extends survivability but sacrifices tempo. Players constantly weigh short-term momentum against long-term system stability.

2.2 Transparent Mechanics

The legality rule (M × A ≥ F) and 2d6 resolution keep outcomes readable and learnable. Players can estimate risk and make informed decisions instead of guessing.

2.3 Entropy Management

Stress accumulates on cannons over time. Players must plan Maintenance windows, rotate firing, and manage risk escalation as systems degrade.

2.4 Fast Resolution

One action per turn, immediate outcomes, minimal bookkeeping. Typical games end in 10–12 minutes across roughly 5–6 turns per player.

2.5 Graduated Risk

Because 2d6 creates a bell curve, risk rises smoothly as σ increases. Players can calculate when to push and when to stabilize.

3. Components

3.1 Cards (49 total)

Offensive Cards (38)

• Stats: M (Mass), A (Acceleration), F (Force Threshold)
• Purpose: Attack enemy shields
• Playability rule: M × A ≥ F

Maintenance Cards (8)

• Type: General Maintenance (dual-purpose)
• Choose one on play: Shield Support or Cannon Support
• Design intent: replaces separate shield-repair and cannon-repair categories

Utility Cards (3)

• Aim, Reroll, Overhaul
• Low count to enforce scarcity and timing value

3.2 Physical Components

• Cannon tokens (6): 3 per player, labeled Cannon 1–3
• Shield tokens (4): 2 per player, each tracks HP (max 4)
• Stress markers (18): 6 per cannon, track σ = 0–6
• Flux tracker (1–2): shared or per player, track Φ from 0+
• Dice: 2d6 for all rolls
• Reference sheets (2): turn structure and outcome reminders

3.3 Box Contents Checklist

• 49 cards (sleeves recommended)
• 6 cannon tokens
• 4 shield tokens (HP trackers)
• 18 stress markers
• 1–2 flux trackers
• 2 six-sided dice
• 2 reference sheets
• 1 rulebook (this document)

4. Setup

4.1 Pre-Game Setup

Prepare the deck

• Shuffle all 49 cards
• Place the deck face down in the center
• Leave space for a discard pile

Seat players

• Sit opposite each other
• Clear space for cannons, shields, and trackers

Set up player components (each player)

• Place 3 cannon tokens; set each cannon to σ = 0
• Place 2 shield tokens; set each shield to HP = 4
• Set Φ = 0 (or set the shared tracker to 0)

Draw opening hands

• Deal 5 cards to each player
• Keep hands hidden

Choose starting player

• Randomly determine who goes first

4.2 Setup Diagram

PLAYER 1 ═══════════════════════════════════ [Cannon 1: σ0] [Cannon 2: σ0] [Cannon 3: σ0] [Shield A: 4HP] [Shield B: 4HP] Flux: 0 Hand: 5 cards (hidden) [DECK] [DISCARD] Dice: 2d6 PLAYER 2 ═══════════════════════════════════ [Cannon 1: σ0] [Cannon 2: σ0] [Cannon 3: σ0] [Shield A: 4HP] [Shield B: 4HP] Flux: 0 Hand: 5 cards (hidden) Setup Time: 2–3 minutes

5. Core Mechanics Overview

5.1 The Three Resources

Cannons (Offense)

• 3 per player; each cannon tracks σ independently
• Fire Offensive cards
• Permanently removed when destroyed

Shields (Defense)

• 2 per player; each shield has 4 HP
• Absorb all incoming damage before cannons
• Permanently removed when destroyed

Cards (Tactical Options)

• Hand size: 5
• Play 1 card per turn
• Draw back to 5 at end of turn

5.2 Turn Loop (Procedure)

1. Choose an action: Fire / Maintenance / Utility
2. Resolve immediately (roll only if firing)
3. Update σ, Φ, and shield HP as required
4. Discard played card(s)
5. Draw back to 5
6. Pass turn

5.3 Primary Win Condition

Destroy both enemy shields while retaining at least one operational cannon.

6. Prototype Testing and Classroom Playtest

6.1 Testing Context

• Environment: High-school physics classroom (block schedule)
• Session length: 85 minutes
• Format: Rapid teach → supervised play → independent play → debrief and survey

6.2 Participants

• Player profile: High-school physics students; mixed arithmetic fluency and strategy experience
• Grouping: Rotating pairs; multiple matches run in parallel

6.3 Methodology (85-Minute Block Protocol)

1. Setup and distribution (5 minutes)
• Hand out decks and tokens, assign pairs, seat players, clear space
2. Rules teach and first-turn demo (12 minutes)
• Teach the core loop, legality rule (M × A ≥ F), and the purpose of σ/Φ
• Demonstrate one full turn, including updates and redraw
3. Supervised matches (18 minutes)
• Pairs play initial matches with active facilitation
• Designer logs confusion points, timing pressure, and common illegal plays
4. Independent matches (35 minutes)
• Pairs run repeated matches with minimal intervention
• Observation focus: pace vs the 10–12 minute target, cannon rotation behavior, Maintenance usage, and endgame clarity
5. Debrief and quick survey (10 minutes)
• Short written prompts: clarity, fun, perceived agency, most confusing rule, suggested improvements
6. Pack-up and note capture (5 minutes)
• Collect components; consolidate notes and tag iteration decisions

6.4 What Was Measured

• Learnability: time to first legal action; recurring rule questions
• Pace: observed match length versus 10–12 minute target
• Decision quality: rotation frequency; Maintenance timing; willingness to push at higher σ
• Clarity: which terms/rules produced repeat confusion (σ, Φ, legality rule, damage flow)
• Balance signals: shield break patterns; cannon losses; runaway leads vs recovery chances

6.5 Changes Driven by Playtest (Qualitative Evidence)

Classroom play revealed two recurring friction points: (1) players delaying the Maintenance mode decision, and (2) missed σ/Φ updates during fast turns. The rules and aids were revised accordingly: Maintenance now requires choosing Shield Support or Cannon Support at the moment the card is played, and the reference sheet now includes a turn-end checklist (“Update σ/Φ → Apply damage/HP → Discard → Draw to 5”). These changes reduced table stoppages while preserving the intended push-versus-stabilize tension.

6.6 Outcomes (Portfolio Summary)

• The core loop (Fire vs Maintenance vs Utility) remained stable under both supervised and independent play.
• The design sustained repeatable play within an 85-minute block (teach + multiple matches + debrief).
• Iterations improved rules clarity and reduced recurring stall points without changing the underlying strategic arc (rotation, timing, risk management).
• Session notes and revision artifacts are available on request as supporting evidence.

© 2025–2026 Guillermo Ithier. All rights reserved. • PORTFOLIO COPY—EVALUATION ONLY
Document ID: PW-GDD-v2.0-2025-11-02