Rest in PeaceRest in Peace | Art By: Jason Rainville

Hello, everyone! Welcome back to Commander: What If? In this series we explore changes to the Commander format and the ripple effects they would have on the game as a whole. This time we are asking the question, “What if Commander had a sideboard?” This idea of adding a sideboard to Commander seems simple enough, but as week dig into this idea, it's clear that there is more to this than meets the eye. Let's begin!

Sideboards

For those who might not know, a sideboard is a set of fifteen cards that can be swapped into the main deck for the second or third game of a match. Typically these cards are trump cards for specific matchups or situational removal that would otherwise be too narrow to justify in the main deck. For example, if a reanimator deck is popular in the meta, a sideboard might include Relic of ProgenitusRelic of Progenitus to remove cards from their graveyard to shut down their plans. Against an artifact combo, one might bring in Null RodNull Rod or Stony SilenceStony Silence to shut down the activated abilities of artifacts. In sixty-card formats, sideboards work well because games are usually played in a best-of-three structure where players can better tune their decks as they learn more about what the opponent is trying to do. The issue in Commander is that this format is almost always best of one in a casual setting, which raises the first big question: when would the actual opportunity to swap cards arise?

To make sideboards functionally work for this discussion, let’s imagine there is a Commanders Revealed phase at the start of each game. During this phase, players could swap cards into their decks based solely on what commanders are revealed at the table. For example, if you are in mono-red and see that everyone else is on one or two colors only, you might decide to remove Blood MoonBlood Moon since it is less likely to have much impact. On the other hand, if you see multiple three-color decks, Blood MoonBlood Moon suddenly becomes a must-keep. In playgroups that know each other’s decks well, sideboarding would be even more impactful since players would be familiar with what they are actually up against and can plan accordingly. With this rule in place, let’s explore what Commander with sideboards could look like.

The Secret Commander archetype would become much more tactical than just a fun gimmick

Normally, a secret commander is used to give a deck a twist or to sneak in access to additional colors. If sideboarding is allowed, though, the strategy gets much stronger. If opponents are making sideboarding choices based solely on the visible commander, they may completely miss what your deck is actually doing. Someone might see Tatyova, Benthic DruidTatyova, Benthic Druid and assume they should bring in land hate, only to discover the deck is really built around Jolrael, Voice of ZhalfirJolrael, Voice of Zhalfir and simply wants to keep a massive hand and attack with flying land creatures. If players can tech against one another but can't bring anything in for the hidden commander, that deck suddenly has an advantage out the gate.

Rule Zero/Pregame Discussions would get... awkward

Commander runs on communication and expectation-setting before games. If players are allowed to bring in sideboard cards specifically to shut down other decks, then honesty during Rule Zero becomes somewhat of a liability in a weird way. Imagine a player brings Urza, Prince of KroogUrza, Prince of Kroog and explains that their plan is to make infinite mana and turn it into a robot army. With that information revealed, the table can easily sideboard in Pithing NeedlePithing Needle, Null RodNull Rod, or Stony SilenceStony Silence to shut down Urza's game before it even starts. That puts the Urza player in a tough spot: do they tell the truth and risk being hated out, or do they withhold details?

This creates a conflict. Commander is supposed to be about openness and social contracts, but sideboards reward secrecy. Even worse, there may be situations where a player discovers a combo or synergy mid-game they did not even know about beforehand. From the outside, this could look shady when it was just genuine discovery. The risk of players feeling deceived or pressured to lie would hang over every game.

Eldrazi and Lessons: old mechanics find a new home

Commander has no “outside the game” rules like constructed formats do, which means mechanics designed to work with sideboards have been almost unusable. Lessons from Strixhaven: School of Mages are a perfect example. In sixty-card formats, players could cast a spell with learn and then pull a Lesson card from their sideboard to their hand. A more common example of this is from Pauper with the deck Moggwarts playing First Day of ClassFirst Day of Class, which can get Introduction to ProphecyIntroduction to Prophecy from the sideboard for free. Commander has never been able to replicate that experience, which is a shame since Lessons offer a nice low-powered toolbox. They can tutor lands, create tokens, draw cards, or remove permanents, all in simple and flavorful ways. With sideboards, suddenly an entire Learn and Lesson subtheme becomes possible in Commander.

Spawnsire of UlamogSpawnsire of Ulamog is another obvious winner. Currently, the card sees play either as an Eldrazi to fill out a kindred deck or as a way to generate tokens for commanders like Raggadragga, Goreguts BossRaggadragga, Goreguts Boss. But if its final ability could actually unleash an entire sideboard of Eldrazi, it would become one of the flashiest win conditions ever printed. Imagine activating Spawnsire and dumping out Ulamog, Kozilek, Emrakul, and their friends all at once. That is the kind of overkill finish that Commander was made for.

Wish tutors would explode in popularity

Cards like Burning WishBurning Wish, Glittering WishGlittering Wish, Living WishLiving Wish, and Death WishDeath Wish would become incredibly strong in Commander. These cards let you grab the exact tool you need from your sideboard, which is far more consistent than hoping to draw it naturally. For example, it would be possible keep combo pieces safe from cards like Sadistic SacramentSadistic Sacrament by storing them in the sideboard until the coast is clear. This would also protect the card from being milled or stolen with a card like Bribery since the card technically wouldn't be in the ninety-nine. Since wish effects do not search libraries, they also dodge powerful hate pieces, like Opposition AgentOpposition Agent. Once sideboards exist, wish cards would become staples for Commander overnight. 

Hatebears and stax pieces would be more common

Sideboards are perfect for housing narrow but devastating hate cards. Stax decks could tailor their lock pieces to each pod while removing stax pieces that won't be relevant. Facing a toolbox deck? Bring in Opposition AgentOpposition Agent. Sitting across from an enchantress player that's about to take an hour of your time that you can't get back? Swap in Aura of SilenceAura of Silence and Back to NatureBack to Nature. Playing against graveyard recursion? Load up on Rest in PeaceRest in Peace, Scavenger GroundsScavenger Grounds, or Soul-Guide LanternSoul-Guide Lantern. Even non-stax decks would take advantage of this flexibility, which would make hatebears and prison pieces much more common overall.

Brick cards would be a thing of the past

A Brick card is a card that is drawn for a game that is effectively useless. Cards like Carpet of FlowersCarpet of Flowers or PyroblastPyroblast are powerful in the right pod but useless in the wrong one. Sideboards can fix this problem. You could confidently run Carpet of FlowersCarpet of Flowers knowing you can swap it out if no one is playing blue. You could keep PyroblastPyroblast in your deck as a fantastic removal piece against either blue spells or permanents . This safety net would make situational powerhouses more attractive to deckbuilders since in the worst case scenario, they can simply be pull out for something more relevant. (Please note, I love Carpet of Flowers and Pyroblast and play both of them. There are games in which they are stronger than others.)

The same goes for hyper-specific removal. The ElderspellThe Elderspell is rarely worth including in most decks since planeswalkers are not always present, but against a superfriends deck, like Commodore GuffCommodore Guff, it's devastating. Sideboards let players bring these wild silver bullets into play for the perfect matchup, which can create some unforgettable Commander stories.

Tutors would become more important than ever

When you bring a card in from the sideboard, you want to see it. Tutors would become the bridge between your main deck and your sideboard. Demonic TutorDemonic Tutor and Vampiric TutorVampiric Tutor would get even stronger, but even narrow tutors would gain another layer of relevance. Using a card like Tribute MageTribute Mage to get Damping SphereDamping Sphere to slow down that storm deck will work like a charm and the table is fully aware of the intentions behind it. Sideboards would push tutors even further into the spotlight and give more of a purpose than just finding a win condition or board wipe.

Players would have to become better deckbuilders

One of the most important lessons for new Commander players is that every deck has weaknesses. With sideboards, those weaknesses would be tested more often since players can swap a card into their deck specifically to stop certain plays. Deckbuilders would have to plan not only for general interaction, but also for specific hate pieces that might appear more frequently. This would encourage players to think more critically about their win conditions and their backup plans if they want to have a chance at winning the game.

In constructed formats, players expect sideboards and plan accordingly. They know that their burn deck will face life gain or that their combo deck will face graveyard hate. Commander players, however, are used to building more broadly, covering bases in the ninety-nine rather than anticipating targeted hate. With sideboards, that dynamic changes drastically.

The average game would go longer

Runaway games often happen in Commander when someone presents a problematic creature or spell to the table that no one else can answer. A Uril, the MiststalkerUril, the Miststalker Voltron deck can easily steal games if opponents are light on removal. With sideboards, those decks would run into more consistent answers, slowing down the format. This would make games grindier, with more back-and-forth exchanges. It would also give room for bigger spells and higher-cost strategies since players could actually survive long enough to cast them.

The format would feel more competitive

At its core, a sideboard is a competitive tool. Its purpose is to give you an edge against specific strategies. Adding that to Commander would make the format more competitive across the board. In cEDH or bracket four, this could revolutionize deckbuilding by giving players extra flexibility. In more casual brackets, though, it could feel unhealthy. Sideboards create an environment where players always need to be ready for hate, which undermines the creative and social side of the game.

Wrapping Up

In a format where the intent is to play casually, adding another competitive element like sideboards is a strange prospect. When I first started thinking about this question, I assumed there was no merit at all. But after looking more closely, I realized there are some interesting upsides. Mechanics like wish and learn could finally function as intended, narrow cards could shine in the right moments, and flashy win conditions like Spawnsire of Ulamog would be possible to pull off in Commander. Best of all, this could drastically reside the number of blow out games a playground would experience. 

Even so, I think the negatives outweigh the positives. The strain on Rule Zero, the temptation to withhold information, and the pressure to build with competitiveness in mind all push Commander away from what makes it special. At its core a big part of Commander deck design is trying to cram all the answers you need into one deck in a way where everything still runs smoothly. While sideboards could open new doors for gameplay, they also risk shutting down the social, experimental, and creative nature of the format.

For me, that tradeoff is not worth it. But what about you? Would you ever try Commander with sideboards just to see what it would be like? Do you think it would add to the format or take away from it? Let me know in the comments, and until next time, happy brewing!