I know sideboards may not seem that useful in that commander, since you have an already larger than normal deck, you should have enough room for all the cards you need, right? But like the standard format, certain cards are needed to be effective against certain matchups. I don’t usually sideboard because I don’t remember the last time I had a short game of EDH. But they may be useful in competitive 1 on 1 commander games. So, I’ve tried to come up with some good sideboard cards for some of the more popular archetypes.
Against Artifact Decks
Vandalblast is an awesome board wipe against Artifact matchups such as Sharuum the Hegemon or Memnarch, It can be used to destroy an artifact for a single red mana, or all artifacts you don’t control for five mana, it’s also commonly used as a finisher when mixed with Massacre Wurm and Mycosynth Lattice.
Hum of the Radix
This card does the opposite of the affinity effect making artifacts more expensive for each artifact a player controls. This can put an insanely high tax on even the cheapest of artifacts
Against Mono-Color Decks
Iona, Shield of Emeria
In my opinion, this creature should be banned along with Deadeye Navigator and Palinchron. Iona can shut down the strongest colour of any deck just by sitting there, and even then she can be flickered out to choose another colour if that becomes a problem.
This spell is very useful against mono-color wiping out entire creature board states. It focuses on creatures so it’s probably not as useful as Iona but it can definitely clear a path
Against Creature Tokens
The mana cost of creature tokens is 0, so you don’t even have to put counters on this for it to be devastating to creature token decks.
Sever the Bloodline
This is effective against a huge group of creature tokens with the same name. If a creature token deck focuses on producing a single type of token such as Eldrazi Spawns or Saprolings then this card is what you need.
Since tokens fizzle when exiled or destroyed, throwing one of these down engulfs a large group of tokens with the same name much like Sever the Bloodline. Unlike sever though it is very difficult to recur.
Illness in the Ranks/Virulent Plague
Anything that deals small amount of damage to a large amount of creatures will do but these focus on creature tokens and they shut down some of the smaller tokens.
Erebos, God of the Dead
Completely shuts down your opponent’s life gain, also allows you to draw cards for a small amount of your own life. Also, it’s very difficult to get rid of.
I would say Tainted Remedy over Rain of Gore, Leyline of Punishment or Havoc Festival because apart from the former they all stop you from gaining life as well as your opponents.
I was recently reminded of this creature. If he deals combat damage to a player, he gives them an emblem that disables any life gain, it can’t be removed unlike the others. Pretty evil
Easily one of the most useful cards in EDH. If you can get this off at an early stage of the game, you can steal the combo pieces long before the opponent can tutor for them and get rid of them for ever.if you can get to 10 mana pretty quick you can pretty much devastate the deck.
This may only allow you to steal one of the combo pieces, but it stops them from having it, and what’s more you can use it if it benefits you.
This only works if the combo has pieces that are sorcery speed, if all of the pieces are instant speed you may have to mix in a Render Silent or Silence to stop them from casting spells or a Trickbind or Stifle to stop activated abilities. But I have stopped a few combos with this card
Against ETB/Entry Hazard decks
Torpor Orb/Hushwing Gryff
These two completely stop entry hazards such as Purphoros, God of the Forge and Warstorm Surge. It also stops other annoying abilities such as Ashen Rider and Acidic Slime which is also very good.
These two stop a triggered ability at a pinch which may be useful to stop an Ashen Rider from exiling your stuff or a Child of Alara (aka Angry Baby) from destroying everything.
I think quite a lot of these cards would probably be main board anyway. But I’ve had quite a few times where I’ve have needed a few more cards to cope with some situations but have struggled to find anything in the deck to supplant because everything had its place. I do hope you find this useful and happy deck building.