Practice · sideboarding

You lost the first game, and now you know what your opponent is playing and which part of it beat you. Choose what comes out of the deck and what comes in from the sideboard.

What a sideboard is for

• It is a list of answers, not of good cards. A card that is too situational to play blind is exactly the card to keep for the situation. The guide puts the same thought the other way round: a removal spell with a narrow target is judged weak on frequency, and that is why it rests on the sideboard rather than in the deck.
• You board against what beat you, not against what you saw. A deck has a look — artifacts, enchantments, a graveyard, a swarm of tokens — and it has a reason it won. They are often not the same thing, and the card that matches the look is the one your hand reaches for first.
• Every board here carries one of those. It matches what their deck is made of, and it answers nothing about what beat you. Finding it is the exercise.
• Only your colours. Everything shown came out of your own pool and can be cast in the deck you are already playing; the question is never mana, only which answer.
• The cards you did not understand are the ones that lose the match. The guide’s own example is two cards left in a sideboard by a player who never worked out what they did.

This exercise practises The Secrets of Sealed, Part II.