mtg_python_deckbuilder/docs/user_guides/batch_build_compare.md

Build X and Compare User Guide

Overview

The Build X and Compare feature allows you to build multiple decks using the same configuration and compare the results side-by-side. This is useful for:

• Seeing variance: Understand which cards are consistent vs. which cards vary due to RNG
• Finding optimal builds: Compare multiple results to pick the best deck
• Analyzing synergies: Use the Synergy Builder to create an optimized "best-of" deck

Quick Start

1. Build Multiple Decks

1. Click New Deck to open the deck builder modal
2. Configure your commander, themes, ideals, and bracket as normal
3. At the bottom of the modal, adjust the "Number of decks to build" slider (1-10)
   • Setting this to 2 or more enables batch build mode
4. Click Quick Build - the "Create" button is hidden for batch builds

Note: All builds use the exact same configuration. There are no variations in commander, themes, or ideals - you're simply running the same build multiple times to see different card selections.

2. Track Progress

After starting a batch build, you'll see a progress screen showing:

• Progress bar: Visual indicator of completion
• Build status: "Completed X of Y builds..."
• Time estimate: Dynamically adjusted based on commander color count
  • 1-2 colors: 1-3 minutes
  • 3 colors: 2-4 minutes
  • 4-5 colors: 3-5 minutes
• First deck time: The first deck takes ~55-60% of total time

3. Compare Results

Once all builds complete, you'll be redirected to the Comparison View with:

Overview Stats

• Unique Cards Total: All different cards across all builds
• In All Builds: Cards that appear in every single deck
• In Most Builds (80%+): High-frequency cards
• In Some Builds: Medium-frequency cards
• In Few Builds: Low-frequency cards

Most Common Cards

Shows the top 20 cards by appearance frequency, excluding guaranteed cards like:

• Basic lands
• Staple lands (Command Tower, Reliquary Tower, etc.)
• Must-include cards (if using the include/exclude feature)
• Fetch lands

Tip: Hover over any card name to see the card image!

Individual Build Summaries

Each build shows:

• Total card count and breakdown (Creatures, Lands, Artifacts, etc.)
• Expandable card list with full deck contents

Using the Synergy Builder

The Synergy Builder analyzes all builds and creates an optimized "best-of" deck using the most synergistic cards.

How It Works

The Synergy Builder scores each card based on:

1. Frequency (50%): How often the card appears across builds
   • Cards in 80%+ of builds get a 10% bonus
2. EDHREC Rank (25%): Community popularity data
3. Theme Tags (25%): Alignment with your chosen themes

Building a Synergy Deck

1. From the comparison view, click ✨ Build Synergy Deck
2. Wait a few seconds while the synergy deck is generated
3. Review the results:
   • Synergy Preview: Shows the full deck with color-coded synergy scores
     • 🟢 Green (80-100): High synergy
     • 🔵 Blue (60-79): Good synergy
     • 🟡 Yellow (40-59): Medium synergy
     • 🟠 Orange (20-39): Low synergy
     • 🔴 Red (0-19): Very low synergy
   • Cards are organized by type (Creature, Artifact, Enchantment, etc.)
   • Each section can be expanded/collapsed for easier viewing

Exporting the Synergy Deck

1. Click Export Synergy Deck at the bottom of the synergy preview
2. Warning: This will delete the individual batch build files and disable batch export
3. Confirm the export to download a ZIP containing:
   • SynergyDeck_CommanderName.csv: Deck list in CSV format
   • SynergyDeck_CommanderName.txt: Plain text deck list
   • summary.json: Deck statistics and metadata
   • compliance.json: Bracket compliance information
   • synergy_metadata.json: Synergy scores and build source data

Additional Actions

Rebuild X Times

Click 🔄 Rebuild Xx to run the same configuration again with the same build count. This creates a new batch and redirects to the progress page.

Export All Decks

Click Export All Decks as ZIP to download all individual build files as a ZIP archive containing:

• CSV and TXT files for each build (Build_1_CommanderName.csv, etc.)
• batch_summary.json with metadata

Note: This button is disabled after exporting a synergy deck.

Performance Notes

• Parallel execution: Builds run concurrently (max 5 at a time) for faster results
• Build time scales: More colors = longer build times
  • Mono/dual color: ~1 minute per 10 builds
  • 3 colors: ~2-3 minutes per 10 builds
  • 4-5 colors: ~3-4 minutes per 10 builds
• First deck overhead: The first deck in a batch takes longer due to setup

Feature Flag

To disable this feature entirely, set ENABLE_BATCH_BUILD=0 in your environment variables or .env file. This will:

• Hide the "Number of decks to build" slider
• Force all builds to be single-deck builds
• Hide comparison and synergy features

Tips & Best Practices

1. Start small: Try 3-5 builds first to get a feel for variance
2. Use for optimization: Build 5-10 decks and pick the best result
3. Check consistency: Cards appearing in 80%+ of builds are core to your strategy
4. Analyze variance: Cards appearing in <50% of builds might be too situational
5. Synergy builder: Best results with 5-10 source builds
6. Export early: Export individual builds before creating synergy deck if you want both

Troubleshooting

Builds are slow

• Check your commander's color count - 4-5 color decks take longer
• System resources - close other applications
• First build takes longest - wait for completion before judging speed

All builds look identical

• Rare but possible - try adjusting themes or ideals for more variety
• Check if you're using strict constraints (e.g., "owned cards only" with limited pool)

Synergy deck doesn't meet ideals

• The synergy builder aims for ±2 cards per category
• If source builds don't have enough variety, it may relax constraints
• Try building more source decks (7-10) for better card pool

Export button disabled

• You've already exported a synergy deck, which deletes individual batch files
• Click "Rebuild Xx" to create a new batch if you need the files again

See Also

• Docker Setup Guide - Environment variables and configuration
• README - General project documentation
• Changelog - Feature updates and changes