essence-wars 0.8.7

High-performance card game environment

A deterministic, perfect-information strategy card game designed for AI research

Quick Start • Features • Project Structure • Documentation • Contributing

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What is Essence Wars?

Essence Wars is a strategic two-player card game engine with a focus on:

• Perfect Information — Both players see all cards, including hands and decks. Victory comes from outthinking your opponent, not luck.
• Deterministic Execution — Seeded RNG ensures every game is reproducible, perfect for AI training and analysis.
• Lane-Based Combat — Creatures occupy board positions, creating spatial strategy alongside card selection.
• ML-Ready Design — 328-float state tensors, 256 discrete actions, and high-performance Rust engine (~33k games/sec).

Features

Desktop Application

Full-featured Tauri desktop client with Human vs AI, Spectator mode, Replays, Deck Builder, and Tutorial.

AI & Machine Learning

• Multiple Bot Types — Random, Greedy (28 tunable weights), MCTS, Alpha-Beta search
• Python ML Framework — Gymnasium/PettingZoo environments, PPO, AlphaZero, Card2Vec
• Training Infrastructure — Callbacks, experiment tracking, Elo ratings, HTML reports

Claude Code Integration

Play Essence Wars directly in Claude Code via MCP (Model Context Protocol):

• Natural language game control
• AI move recommendations with analysis
• Live game visualization in Tauri UI

Quick Start

Play the Desktop App

# Clone and build
git clone https://github.com/christianwissmann85/essence-wars
cd essence-wars
cargo build --release

# Launch the UI
cd crates/essence-wars-ui
pnpm install && pnpm tauri:dev

Train ML Agents (Python)

# Install Python package
pip install essence-wars[train]

# Train a PPO agent
essence-wars train ppo --timesteps 500000

# Benchmark against baselines
essence-wars benchmark --checkpoint model.pt

Play via Claude Code (MCP)

Add to your .mcp.json:

{
  "mcpServers": {
    "essence-wars": {
      "command": "./target/release/essence-wars-mcp"
    }
  }
}

Then in Claude Code: "Start a game with the Iron Wall deck against Swarm Aggro"

Project Structure

essence-wars/
├── crates/
│   ├── cardgame/           # Core game engine (Rust)
│   ├── essence-wars-ui/    # Desktop app (Tauri + Svelte)
│   └── essence-wars-mcp/   # MCP server for Claude Code
├── python/                 # ML agents & training (PyTorch)
├── data/
│   ├── cards/              # Card definitions (YAML)
│   ├── decks/              # Deck definitions (TOML)
│   └── weights/            # Bot weight files
└── docs/                   # Documentation

Component	Description	README
cardgame	High-performance game engine, bots, CLI tools	README
essence-wars-ui	Cross-platform desktop client	README
essence-wars-mcp	MCP server for Claude Code	README
python	ML agents, training, benchmarking	README

Three Factions

Faction	Identity	Keywords
Argentum Combine	Defense & durability	Guard, Shield, Fortify, Piercing
Symbiote Circles	Aggressive tempo	Rush, Lethal, Regenerate, Volatile
Obsidion Syndicate	Burst damage	Lifesteal, Stealth, Quick, Charge

Plus Neutral cards and 12 unique Commanders with passive abilities.

Documentation

Game Design

• Game Rules — Complete rules, keywords, card types
• Lore & World — Faction history and characters

Art & Assets

• Style Guide — Visual design guidelines
• Asset Generation — AI-assisted art pipeline

ML & AI

• Bot System — Bot architecture, weight tuning
• Training Pipeline — PPO, AlphaZero, behavioral cloning
• Ratings System — Elo tracking for decks and agents

Development

• CLI Reference — Command-line tools
• Reporting — Analysis and visualization

Performance

Metric	Value
Random games	~33,000/sec
Greedy bot games	~4,300/sec
MCTS (100 sims)	~22ms/move
Engine state clone	~245 ns
State tensor encode	~158 ns

Commands

# Build & Test
cargo build --release                    # Full workspace
cargo nextest run --status-level=fail    # Rust tests
uv run pytest python/tests               # Python tests

# Lint
cargo lint                               # Rust (clippy)
uv run mypy python/essence_wars          # Python types
pnpm run check                           # Svelte/TS (in UI crate)

# Game Tools
cargo run --release --bin arena --       # Bot matches
cargo run --release --bin validate --    # Quick balance check
cargo run --release --bin benchmark --   # Thorough analysis
cargo run --release --bin swiss --       # Tournament mode

Contributing

Contributions are welcome! This project uses:

• Rust for the core engine and desktop backend
• Svelte 5 (with runes) for the desktop frontend
• Python for ML agents and training

Each crate has its own CLAUDE.md with AI-developer context and README.md with human contributor documentation.

Development Setup

# Rust
cargo build --release

# Python (using uv)
uv sync --all-groups
uv run pytest python/tests

# UI (using pnpm)
cd crates/essence-wars-ui
pnpm install
pnpm tauri:dev

Citation

If you use Essence Wars in your research, please cite:

@software{essence_wars,
  title = {Essence Wars: A High-Performance Card Game Environment for RL Research},
  author = {Wissmann, Christian},
  year = {2025},
  url = {https://github.com/christianwissmann85/essence-wars}
}

License

MIT License — see LICENSE for details.

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Built with Rust, Svelte, and PyTorch
Designed for humans and AIs alike