How to upgrade a Commander precon

Start with a complete stock list, protect the cards that make the deck yours, and buy a small package that fixes its weakest roles.

1. Load a stock list or export your precon as text. Choose the intended commander and check the parsed card count.
2. Set a purchase budget. Add cards you already own and protect the commander’s engines.
3. Review draw, ramp, interaction, and land count before choosing upgrades. A card can contribute to multiple roles.
4. Compare each suggested addition with its cut. Check mana value, rules restrictions, and synergy with the commander.
5. Apply selected changes, export the edited list, and playtest. Reopen the saved draft for the next iteration.

What the method checks

Commander color identity, current Commander legality, duplicate singleton cards, protected cards, cumulative purchase cost, existing cards, and the selected table’s Game Changer constraint. Spell-role and theme matching remain heuristics; inspect the actual rules text.

Example workflow

Use the real Reap the Tides precon example in the tool. Compare a $25 package with a $50 package, select the changes you would play, and reanalyze the edited list. The live result depends on current prices and the stock list.

Can this tool guarantee a winning or correctly rated deck?

No. It produces a review plan using live card data, role heuristics, and constraints. Decisions about synergy, play patterns, and table intent require player review.

Do I need an account?

No. Drafts and recent review inputs stay on your device. Shared links carry the deck list; the recipient runs a fresh analysis.

How are prices and owned cards handled?

Scryfall nonfoil prices are estimates. Owned additions have no purchase cost. Shipping, tax, and sales of removed cards are not included.

Sources

• Scryfall card data and pricing
• MTGJSON stock deck data
• Current Commander format and brackets

Method reviewed October 7, 2026.