Commander is one of the most popular ways to play Magic: The Gathering. Instead of the usual 60-card decks and one-on-one battles, Commander is typically a casual, multiplayer format where four players face off in a free-for-all. It's known for splashy plays, wild board states, and a focus on fun.

The format is built around a single legendary creature who acts as your deck's leader: your commander. This one card defines the strategy and style of your entire deck.

Every Commander deck has two core rules for its composition. First, your deck must contain exactly 100 cards. This includes your commander.

Second, it's a "singleton" format. This means that other than basic lands (Plains, Islands, Swamps, Mountains, and Forests), you can only have one copy of any given card in your deck. This variety makes games unpredictable and exciting.

Your commander doesn't start in your deck. Instead, it sits in a special game area called the Command Zone. You can cast your commander from the command zone for its normal mana cost. If it dies or is exiled, you can choose to return it to the command zone instead of the graveyard or exile.

There's a catch, though. Each time you cast your commander from the command zone after the first, it costs an additional two generic mana ($2$). This is called the "commander tax." So, the second time you cast it, it costs its normal cost plus $2$. The third time, it costs its normal cost plus $4$, and so on. This keeps even the most powerful commanders from dominating the game completely.

There's also a special win condition. If a player takes 21 or more combat damage from a single commander over the course of the game, that player loses.

The most important rule in building a Commander deck is color identity. Your commander's color identity determines which cards you're allowed to put in your deck.

A card's color identity includes every mana symbol that appears on the card—not just in its casting cost, but anywhere in its rules text as well. For example, a creature that costs green mana but has an ability that requires blue mana has a green and blue color identity.

Every single card in your 99-card deck must have a color identity that is a subset of your commander's. If your commander is only red, you can only play cards that are red or colorless. If your commander is white, blue, and black, you can play any card that is white, blue, black, or any combination of those three colors, plus colorless cards.

Even lands are affected. You can't put a land that can produce black mana, like a Swamp or a land that says "tap to add $B$", in a deck whose commander doesn't have black in its color identity. This simple rule is the foundation of all deckbuilding in the format, creating a powerful link between your commander and the deck it leads.

Ready to test your knowledge? Let's see what you've learned about the rules of command.

And that's it! With these rules, you have the foundation to build your first Commander deck. Choose a legend that inspires you and start brewing.