Card Game Prototype Specification

Game overview

Item	Details
Working title	Grid Tactics
Genre	TCG/DCG-style card game
Match format	CPU battles only
Platform	Web browser (PC)
Setting	Classic fantasy

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Core rules

Win condition

Reduce the opposing player’s HP (10,000) to 0.

Field

• 6x3 grid (6 columns x 3 rows)
• The left 3 columns are your side, and the right 3 columns are the enemy side
• Each player has a home-base tile (for example, the center tile at the far back)

AP (Action Point) system

• Gain 5 AP every turn
• Unused AP can be carried over to the next turn
• Summoning, movement, attacks, and card use all consume AP (cost varies by card)

Turn flow

1. Draw phase: draw 1 card
2. AP phase: gain 5 AP (added to any carried-over AP)
3. Main phase: spend AP to perform actions in any order
4. End phase: end the turn

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Card types

1. Character cards

Units you summon onto the field to fight.

Parameter	Description
HP	Health
ATK	Attack power (roughly 500-3000)
Range	Distance the unit can attack
Movement	Number of tiles the unit can move per turn
Attribute	Fire / Water / Wind / Earth / Light / Dark
Summon cost	AP required to summon
Move cost	AP required to move
Attack cost	AP required to attack
Special ability	Pierce, direct attack, etc.

2. Support cards

• Buffs / debuffs (Attack Up, Defense Down, etc.)
• Damage / recovery (direct damage, HP recovery)
• Special effects (movement, position swap, draw, etc.)
• Use cost: consumes AP

3. Terrain cards

• Placed on specific tiles and apply a persistent effect
• Examples: attack +500 tile, recovery tile, impassable tile

4. Weather cards

• Affect the entire field
• Examples: Fire-attribute damage +20%, everyone’s movement -1

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Attribute system

Four-way matchup (1.5x damage when advantageous)

Fire -> Wind -> Earth -> Water -> Fire

Light and Dark

• Light and Dark are advantageous against Fire, Water, Wind, and Earth (1.5x)
• When Light and Dark clash, both are weak to each other (both deal 1.5x)

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Ways to attack the opponent directly

Method	Description
Reach a specific tile	A character can attack once it reaches the enemy home-base tile
Special ability	Characters with abilities such as “Pierce” or “Direct Attack”
Support card	Direct-damage support cards

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Deck and hand

Item	Value
Deck size	30 cards
Starting hand	6 cards
Cards drawn each turn	1 card

• Graveyard: where defeated characters and used cards go
• Revival cards can bring characters back from the graveyard

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Scope of the prototype

Required features

1. Display the 6x3 field
2. Display player HP (10,000 for both you and the opponent)
3. AP display and management (gain, spend, carry over)
4. Hand display and draw function
5. Summon character cards (from hand to field)
6. Move characters (select a tile within range)
7. Character attacks (range and attribute calculations)
8. Use support cards (buffs, damage, etc.)
9. Place terrain cards
10. Use weather cards
11. Turn progression (player -> CPU -> player…)
12. CPU AI (basic decision-making)
13. Win/loss judgment and game over

Initial card set

Type	Count	Details
Character	8 units	One for each attribute (Fire, Water, Wind, Earth, Light, Dark)
Support	5 cards	Attack Up, recovery, direct damage, draw, etc.
Terrain	2 cards	Attack-boost tile, recovery tile
Weather	2 cards	Attribute-boosting weather

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File structure

public/games/card-game-prototype/
├── index.html
├── style.css
├── game.js          # Main game logic
├── cards.js         # Card data definitions
├── ai.js            # CPU AI
├── ui.js            # UI handling
└── images/          # Card images (to be added later)

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Implementation steps

Step 1: Foundation

• Display the field (6x3 grid) with HTML/CSS
• UI for player HP, AP, and hand area
• Turn display

Step 2: Card system

• Define the card data structure
• Create the initial card set
• Implement hand display and draw functionality

Step 3: Character control

• Summoning (hand -> field)
• Movement (tile selection)
• Attacking (target selection and damage calculation)
• Attribute-matchup damage calculations

Step 4: Support / terrain / weather

• Use support cards
• Place terrain cards
• Apply weather-card effects

Step 5: Game flow

• Turn management
• Win/loss judgment
• Game-end processing

Step 6: CPU AI

• Basic AI (random or simple evaluation)
• Decisions for summoning, movement, and attacks

Step 7: Polish

• Deck-building screen (a fixed deck is also acceptable)
• Game start and retry
• Effects and presentation (simple versions are fine)

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How to verify it

1. Start a local server
2. Open /games/card-game-prototype/index.html
3. Start the game -> confirm the hand is displayed
4. Summon a character -> check whether it appears on the field
5. Move and attack -> confirm damage calculation and attribute matchups
6. CPU turn -> check whether the AI takes actions
7. Win/loss judgment -> confirm the game ends when HP reaches 0