mtg-deck-builder – OpenClaw Skill

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name: mtg-deck-builder description: | Builds Magic: The Gathering Commander/EDH and Duel Commander decks from scratch. Use when the user asks to create or build a deck, suggest cards for a commander or strategy, work with budget (LigaMagic), analyze mana curve or card types, or check card legality. Keywords: MTG, Magic, Commander, EDH, Duel Commander, deck building, Scryfall, LigaMagic.

MTG Deck Builder

Build Commander/EDH and Duel Commander decks using Scryfall API for card data and LigaMagic for Brazilian market prices.

Quick Start

1. Identify format: Commander (multiplayer) or Duel Commander (1v1)
2. Get commander from user or help them choose one
3. Use scryfall_search.py to find cards
4. Check banlist using banlists.md
5. Build deck respecting color identity and deck rules
6. Generate report with deck_report.py

Supported Formats

Format	Life	Deck Size	Commander	Banlist
Commander/EDH	40	100 (including commander)	1 or 2 (partner); Companion only if legal	See banlists.md
Duel Commander	20	100 (including commander)	Exactly 1 legendary creature	See banlists.md; check "banned as commander"

Duel Commander: As of March 2026 the format transitions to a new system; check banlists.md and mtgdc.info for current rules.

Regra Singleton (IMPORTANTE!)

Decks de Commander são singleton: cada carta pode aparecer apenas UMA vez no deck, com exceção de terrenos básicos (Plains, Island, Swamp, Mountain, Forest, Wastes).

Regra: NENHUMA CARTA A NÃO SER Plains, Island, Swamp, Mountain, Forest, Wastes PODEM APARECER MAIS DE UMA VEZ

• ✅ 1x Sol Ring
• ✅ 1x Counterspell
• ✅ 15x Island (terreno básico - pode repetir)
• ❌ 2x Lightning Bolt (não permitido)
• ❌ 4x Reliquary Tower (não permitido)
• ❌ 2x Counterspell

Workflow

1. Understand Request

Extract from user message:

• Format (Commander or Duel Commander)
• Commander choice or strategy theme
• Budget constraint (if any, in BRL using LigaMagic)
• Power level preference (casual/competitive)

2. Validate Commander

• Commander/EDH: 1 commander, or 2 with partner; Companion only if allowed by banlist.
• Duel Commander: Exactly 1 legendary creature; confirm not in "banned as commander" in banlists.md.

python scryfall_search.py --name "Commander Name" --check-commander --format commander

3. Search Cards

Use Scryfall syntax for powerful searches:

python scryfall_search.py --query "ci:wubrg t:creature" --limit 50
python scryfall_search.py --query "o:counter ci:ug t:creature"

4. Check Prices (Optional)

python ligamagic_price.py --card "Sol Ring"

5. Build Deck Structure

Standard Commander deck template:

• 1 Commander
• 35-38 Lands
• 10-12 Ramp/Mana acceleration
• 10 Card draw
• 8-10 Removal (single target + board wipes)
• 30-35 Cards supporting strategy

6. Generate Report

python deck_report.py --deck deck.txt --format commander

Key References

• Scryfall API: See scryfall_api.md for search syntax
• Banlists: See banlists.md for Commander and Duel Commander
• Deck Templates: See deck_templates.md for archetypes
• Metagame Sources: See metagame_sources.md for live data URLs
• Color Identity: A card's color identity includes mana symbols in cost and rules text

Fetching Live Metagame Data

IMPORTANT: Always fetch current metagame data before building competitive decks!

For Duel Commander:

1. Search: mtggoldfish duel commander metagame
2. Fetch: https://www.mtggoldfish.com/metagame/duel_commander
3. Extract top commanders, meta %, prices

For Commander/EDH:

1. Search: site:edhrec.com [commander name]
2. Get recommended cards with synergy scores
3. Check https://edhrec.com/commanders for popular choices

For cEDH:

1. Check: https://cedh-decklist-database.com/
2. Find optimized lists by tier

Budget Building with LigaMagic

When user specifies budget:

1. Search cards normally via Scryfall
2. Get prices via ligamagic_price.py
3. Optimize deck to fit budget
4. Report total cost and suggest upgrades

Output Format

Always provide:

1. Decklist in standard format (quantity + card name)
2. Mana curve visualization
3. Card type distribution
4. Total price (if budget was considered)
5. Key synergies explanation

Example decklist section:

COMMANDER
1 Atraxa, Praetors' Voice

MAINDECK
1 Sol Ring
1 Command Tower
1 Arcane Signet
...
38 Forest

Example report summary: Mana curve (e.g. 0: 5, 1: 8, 2: 12, …), card types (Creatures: 35, Instants: 12, …), total LigaMagic (BRL) if applicable, and 2–3 key synergies with the commander.