Deckbuilding
Who this is for: anyone ready to build their first Commander deck. By the end you’ll know the three hard rules (100 cards, singleton, color identity) and have a beginner-friendly template for how many of each kind of card to run. We separate the rules (non-negotiable) from the heuristics (common guidance you can adjust).
🆕 New players: you do not need to build from scratch on day one — a preconstructed deck is a great start. But understanding these rules makes any deck make sense. 🔁 Returning players: singleton + color identity make Commander deckbuilding feel different from 60-card formats. There are no playsets here. 🎯 Commander-specific: every rule below flows from your commander. Pick the commander first; the deck follows.
The three hard rules
Section titled “The three hard rules”These come straight from the format rules (The Commander covers the mechanics behind them).
1. Exactly 100 cards, including your commander
Section titled “1. Exactly 100 cards, including your commander”Your deck is exactly 100 cards, and your commander counts as one of them. So it’s your commander plus 99 other cards. Not 99, not 101 — exactly 100 total.
2. Singleton — one of each card
Section titled “2. Singleton — one of each card”With the sole exception of basic lands, you may include only one copy of any card (by English name). This is the singleton rule. You can run as many basic Plains, Islands, Swamps, Mountains, and Forests as you like; everything else is a one-of.
🆕 New players: “by name” matters — different cards that happen to do similar things are still different cards, so you can run several similar effects, just not duplicates of the same card.
3. Color identity must fit your commander
Section titled “3. Color identity must fit your commander”Every card in your deck must have a color identity that fits within your commander’s. Recall from The Commander that a card’s color identity is its colors plus any colored mana symbols in its cost and rules text, fixed before the game.
In practice:
- Pick your commander → that locks your allowed colors.
- For every card you consider, check that none of its colored symbols fall outside those colors — including symbols buried in the rules text.
- Colorless cards (no colored symbols anywhere) fit into any deck.
🎯 Commander-specific: this is the single most common deckbuilding mistake for newcomers — including a card whose rules text has an off-color symbol. When in doubt, check the whole card.
A beginner deck template (heuristics, not rules)
Section titled “A beginner deck template (heuristics, not rules)”Everything in this section is common community guidance, not official rules. Treat these as starting dials you’ll tune as you learn — there is no “correct” ratio enforced by the format.
A widely used starting point for a first deck, out of your 99 non-commander cards:
| Category | Rough count | What it does |
|---|---|---|
| Lands | ~36–38 | Your mana base. Too few and you stall; this range is a common safe default. |
| Ramp | ~10 | Extra mana / mana acceleration (mana rocks, mana dorks, land-fetch) to cast bigger things sooner. |
| Card draw | ~10 | Refills your hand so you don’t run out of gas. |
| Removal | ~10–12 | Answers to opponents’ threats — spot removal plus a couple of board wipes. |
| Threats / payoffs | the rest (~30) | Creatures and spells that actually win the game, ideally synergizing with your commander. |
🆕 New players: if you remember nothing else, remember “about a third of your deck is land” and “run some ramp, some draw, and some removal.” Decks that skip those three categories tend to feel clunky.
🔁 Returning players: these proportions assume a singleton, 40-life, multiplayer game — they’re noticeably more land- and ramp-heavy than a 60-card 20-life deck, because games go longer and cost more total mana.
🎯 Commander-specific: the higher the power level you’re aiming for, the more these numbers shift (lower curves, leaner mana, more interaction). Power level and how to talk about it is the subject of Brackets and Rule 0.
A note on the mana curve
Section titled “A note on the mana curve”Your mana curve is the spread of cards by mana cost. A beginner-friendly deck keeps a healthy number of cheap plays so early turns aren’t dead, and tops out at a few expensive payoffs. You don’t need to optimize this on day one — just avoid a deck that’s all expensive cards.
The banned list and Game Changers exist — details in chapter 08
Section titled “The banned list and Game Changers exist — details in chapter 08”Two things will shape what’s legal and what’s appropriate for your table:
- A banned list of cards not allowed in the format, and
- a Game Changers list of especially powerful cards used by the bracket system to gauge a deck’s power level.
Both of these change over time, so this guide deliberately does not hardcode the cards here. The current lists, what they mean, and how brackets and the “Rule 0” conversation work are all covered in Brackets and Rule 0 — always check the live lists there rather than memorizing.
🆕 New players: for a first casual game you’ll rarely brush up against the banned list. Don’t let it intimidate you — just glance at chapter 08 before a more serious game.
Quick recap
Section titled “Quick recap”- Exactly 100 cards, commander included (commander + 99).
- Singleton: one of each card, basic lands excepted.
- Color identity: every card must fit inside your commander’s.
- Heuristics (not rules): ~36–38 lands, ~10 ramp, ~10 draw, ~10–12 removal, rest threats — tune to taste.
- Banned list / Game Changers: real, and they change — see chapter 08; don’t hardcode.
What to read next
Section titled “What to read next”- The mechanics behind these rules → The Commander
- Power level, brackets, banned list, Game Changers → Brackets and Rule 0
- Any unfamiliar term → Glossary
Sources: the 100-card, singleton, and color-identity rules paraphrase the official Commander rules and Comprehensive Rules §903 (SOURCES.md S1, S2, S3 — fact #1). Deck-ratio templates are presented as community heuristics, not official rules. Banned-list and Game Changers specifics are deferred to chapter 08 and not reproduced here (SOURCES.md S4, S6 — facts #5, #6).