In some ways, Limited Magic feels like the purest form of the game. Given its lower power level relative to Constructed, games are often closer and less frequently decided by a single card, combination, or big turn. In games like these, small advantages really add up and it's crucial to use every tool at your disposal. An important one, and one that's often underappreciated, is the sideboard.
You can use your sideboard in Limited to achieve any of the same effects that you can in Constructed. However, I'd like to emphasize a couple that are particularly important.
Perfecting Your Answers
The most useful sideboard cards in Limited are your borderline removal spells. Premium removal spells like Murderous Cut and Suspension Field will be in your main deck anyway, but some removal spells are borderline in terms of their power level (think of expensive ones like Bring Low or Rite of the Serpent) or because they're very specific in what they can kill (such as Windstorm or Naturalize).
Barrage of Boulders is a card that you may or may not choose to put in your main deck based on its ability to prevent your opponent from blocking. However, imagine that in Game 1 your opponent casts a Hordeling Outburst, morphs a Ponyback Brigade, and casts a handful more 1-toughness creatures. Suddenly, Barrage of Boulders becomes a great card that you most certainly want to bring in off the sideboard!
Similarly, you wouldn't think of Windstorm as being a stellar card in Khans of Tarkir Limited. However, it's capable of killing a number of extremely troublesome creatures, including what might be the single most powerful card in the format—Wingmate Roc! Once you see that your opponent has a card like this, you need to be ready to look for an answer in your sideboard.
Along those lines, the most important skill in Limited sideboarding is finding weaker cards that can trade for stronger cards. You won't always have as many rares as your opponents do in Sealed Deck and Booster Draft, and if you want a chance to win even when the packs are stacked against you, you need to be able to use your more everyday tools effectively.
Despise isn't super effective when you're taking away an Alpine Grizzly or a Sage-Eye Harrier. However, it might be one of your only ways to beat an opponent who draws Sarkhan, the Dragonspeaker or Zurgo Helmsmasher. Similarly, Disdainful Stroke, Cancel, and Stubborn Denial offer a game plan for beating the Duneblast or Crater's Claws that might otherwise destroy you.
Any card that can answer a bomb, even if it's in an inefficient or indirect way, is useful in Limited. They're the cards that you'll most often look to during sideboarding.
Slow Matchups and Fast Matchups
In Limited, you typically want to build a balanced deck. You want cards capable of playing both offense and defense, and you want creatures spread out across the mana curve. One reason for this is that you simply don't know ahead of time how fast your opponents' decks will be and you want to be well prepared for everything. However, after sideboarding, you have the ability to gear your deck more for the matchup you're facing.
In Khans Limited, I take great pains to always include at least three creatures that cost less than three mana in my deck. This is because when I play against a fast deck, I want to be able to trade creatures early and avoid falling too far behind. However, once I see that my opponent is playing a slower deck and is incapable of beating me with a quick creature rush, I can choose to throw my policy out the window. I might "get greedy" and sideboard out my cheap creatures for more expensive ones that will be better in a long game.
To replace them, I'll look for anything that can offer me card advantage, even if it's a bit slow, like Dutiful Return. I'll also look for answer cards that are particularly useful in the late game, like Cancel.
On the flip side, if my opponent's deck is very fast, I'll try my best to bring in even more cheap cards so I can trade off early and have the best chance of keeping pace.
Matching Up Powers and Toughnesses
Under the right circumstances, I might even sideboard in something like Firehoof Cavalry, which is a remarkably poor card by most metrics. Despite the general quality of the card, it might be just perfect for trading with the cheap creatures my opponent is attacking me with. Against a deck full of Mardu Hateblades, Leaping Masters, and Mardu Skullhunters, Firehoof Cavalry will find something to trade with and can help me avoid falling behind. It might even trade with a Temur Charger! It doesn't matter that Temur Charger is an uncommon and Firehoof Cavalry is a common; it doesn't matter that Temur Charger is a strong card that someone might take highly in a draft; all that matters is that Firehoof Cavalry has 1 power and Temur Charger has 1 toughness.
Matching up the right powers against the right toughnesses and the right toughnesses against the right powers will give you a huge advantage. It's something you should pay close attention to and be constantly looking for opportunities for. Imagine you're playing an Abzan deck and you're undecided on the 40th card in your deck. Well, if your opponent has Mardu Skullhunters, you want Jeskai Student; if he or she has Hooting Mandrills, you want Archers' Parapet; and if he or she has Snowhorn Riders, you want Rotting Mastodon. Whichever one you choose for your main deck, you should be ready to switch between them during sideboarding.
The same concept applies to aggressive decks. If you want your 2/2 creatures to attack through 3-toughness creatures, you should use Dragonscale Boon. If you want them to attack through 5-toughness creatures, you might sideboard out the Boon for Awaken the Bear.
Sideboarding in Sealed Deck
Sideboarding is most important in Sealed Deck. Remember, in Sealed Deck you don't get to choose what cards you're given, and you're likely to have a lot of strong options even past what winds up in your deck. Every card you don't use comprises your sideboard.
Every possibility mentioned above will come up in Sealed Deck, and often. Adjust your creature base to trump what your opponent has. Augment your card advantage when the matchup is slow and your early defense when the matchup is fast. Look for the perfect answers to take care of your opponents' threats, particularly their bombs.
But that's not all! It's possible in Sealed Deck to completely shift colors or strategies during sideboarding! When you build your deck, you might have an Abzan deck and a Jeskai deck that look pretty close in power level. Perhaps a small factor such as the Jeskai deck having a Cancel might lead you to switch between the two when your opponent has a Duneblast.
A side benefit is keeping your opponent guessing. Imagine you win Game 2 with a flurry of flying creatures. Your opponent might sideboard in Windstorm for Game 3 while you transform completely back into your Abzan deck with few or no flying creatures!
Be aware of all of your sideboarding options in Sealed Deck, and be aware that your opponents might be up to the same tricks.
Sideboarding in Booster Draft
In Draft, you won't have the same level of flexibility as you do in Sealed. If you're drafting an Abzan deck, you almost certainly won't wind up with enough cards to transform into Jeskai. So your sideboard changes will typically be smaller, but that doesn't mean they aren't important!
Sideboarding in Draft features an extra layer of complexity because you actually have to draft your sideboard cards. This is something that's quite important. If there isn't a card that you want to put in your main deck, you still might want to snatch up that Dutiful Return, Naturalize, or Barrage of Boulders just in case you need it later. Look for more detail on this concept in next week's article.
Practice identifying possible sideboard cards and keeping track of what weaknesses your deck might have. A slow Abzan deck with few flying creatures and little removal might really need that Windstorm, and you should put a premium on drafting it, just to have in your sideboard.
General Tips for Sideboarding in Limited
Always look through both your main deck and your sideboard between every game in a tournament match of Limited. This might seem annoying and time consuming, but it's a very good habit to get into. You'll learn quickly, and you'll begin to spot things that you never would have otherwise.
For example, sometimes there's a strong card in your main deck that just happens to not be particularly useful in the matchup. I'd rarely think of cutting Smite the Monstrous from my deck, but if I've played two long games without seeing any 4-toughness creatures, then it's correct to do so.
It doesn't cost you anything to think about your sideboard. It will often result in a small advantage if you sideboard well, and at worst it will accelerate your learning process and train you to think outside the box.
Bring extra sleeves for your sideboard; there are three good reasons to do so. First, and most obviously, it will save you time during sideboarding, which will help you finish your matches in time, and probably just make life more enjoyable for you and your opponent. Second, it will help you remember what cards to consider for your sideboard. Sleeve up that Windstorm and that Rakshasa's Secret before the tournament starts and you'll always remember to give them their due consideration every time! Finally, it will make it harder for your opponent to know exactly what you're doing during sideboarding. If you de-sleeve five cards and replace them with five cards from your sideboard, guess what…your opponent knows you sideboarded in five cards. Now imagine what happens if you switch colors in Sealed Deck without extra sleeves!
Which brings me to my next tip, which is that, even when you don't sideboard, you should at least pretend to. Shuffle a couple of sleeved cards into your deck and then pull them out. This way you keep your opponent guessing. Did you bring in Disdainful Stroke? Did you cut the one that you cast in Game 1? If you make it obvious that you're not changing anything, you're only making things easier on your opponent.
Finally, think about your sideboarding a lot in advance of your matches. When I play a Sealed Deck tournament, I spend the entire day between rounds analyzing my card pool and considering my options. I also ask my friends for their input. Sometimes I realize that I made a mistake in building my deck, and I wind up making a particular sideboard change in every match I play. Other times, I find a good sideboard option for a certain situation that I might not've been able to find on the fly during a match.
Again, it doesn't cost you anything to think about your sideboard. Knowing your options ahead of time can only help you.
Limited Magic is about small decisions adding up to (hopefully) give you a small advantage over your opponents. Your sideboard has the potential to provide a lot of these small advantages if you give it the respect that it deserves and learn to use it well. The next match you play, see what it has to offer you!