Brainstorm
This Legacy staple also has a place in Commander. With access to multiple tutor effects that allow you to search for cards and then shuffle your library, be it from Demonic Tutor or Stoneforge Mystic or Scalding Tarn, Brainstorm gives blue players the chance to get the 2 worst cards out of their hand permanently. This level of instant speed card draw for such a low mana cost allows you to hold it for the best time and react to any spells or effects that your opponent might throw at you. Holding Brainstorm in your hand, especially with a fetchland in play can feel like you're in a definite position of power.Viscera Seer
Sacrifice outlets are always a good option in Commander, so many cards are as great going into or staying in the graveyard as they are in play, plus it gives you the ability to make sure your opponents never gain control of anything you have on board. When coupled with Grave Pact -like effects, you can really damage your opponent’s board. Viscera Seer provides all that for one black mana, with the bonus of being able to scry. In a deck built to take advantage of these strategies, Viscera Seer really shines.Goblin Welder
In most games of Commander, your best artifacts are probably going to get destroyed at some point or another. There are just too many great cards that can blow up your artifacts, from Acidic Slime to Austere Command, it’s hard to keep your toys on the board. Luckily, Goblin Welder can get it back for you, and then some. When you first read the card, you notice the linear strategy I’ve just discussed - trade your less powerful trinket into something menacing. And if you play the card that way forever, it’s still a great card. However, extending beyond that you can do some other cool thing with Goblin Welder. The first one, similar to Viscera Seer’s use, is that you can bin important artifacts you don’t want exiled so that you can get them back later. Better to have your Darksteel Forge in the yard then permanently lost forever. Even better is that you can use it on your opponents. Don’t like the artifact they have in play? Give them the one they have in their graveyard back to them in exchange. How nice of you.Berserk
I almost didn’t have Berserk on the initial list, because that list existed before the spoilers for Conspiracy 2. I didn’t want to promote a very expensive card, but Berserk is very versatile for one green mana. The obvious line of play with it is to just make your attacker twice as large out of nowhere and take someone out of the game, especially if that attacking creature is your Commander. That alone can be pretty powerful. However, Berserk enters the realm of insanity once you realize that it can target any creature. Suddenly, you have a one mana way of getting someone else out of the game off the back of someone else’s creature. Additionally, you can use it as a removal spell of sorts. If a creature you don’t like is swinging in, throw Berserk at it and watch it get destroyed later in the turn. Pretty good for a color that isn’t known for the best instant speed spells.Deathrite Shaman
Deathrite Shaman is a Swiss Army knife when it comes to Commander. Mana ramp? Yep. Life gain? You got it. Life loss from all opponents? It’s got that too. Oh, and it is perfect graveyard hate. It doesn’t make you a cup of coffee, though. Still, that’s a lot of stuff in such a small package. Not to mention that the hybrid mana makes it easier to cast. You would think this thing should be a 0/1 like Birds of Paradise, but nope, it's a ½. This card was so pushed, it got banned in Modern for a reason. Luckily, it’s perfectly ok to play in Commander!
Codex Shredder
Yes, I know colorless spells are packed at 1 CMC. But we all already know that Skullclamp and Sensei’s Divining Top are absolutely nuts. So I decided to give you a less-known 1 CMC artifact. Codex Shredder does more than you think. For one, decks that love self-mill, like Sidisi, Brood Tyrant love effects like this. Other decks that interact with their graveyard can almost see this as “Tap: Draw a card.” Beyond that, it’s a Regrowth effect that every deck can run. In those decks, Codex Shredder will get you 5+ cards at times to chose from later. Additionally, this card messes with anyone trying to use top of the library tutors like Enlightened Tutor.
Mother of Runes
Mom, as everyone calls this card, can do so much for your deck, both on offence and defence. On the aggressive side of things, Mother of Runes allows your best creature to get in without worry of blockers. This is great when you are running a commander like Karlov, where you may not have many Voltron pieces to help push through damage. Mother of Runes it also a great counterspell in a way, seeing as how she can stop harmful spells from touching your creatures. Additionally, she can turn one of your creatures into a super blocker, including herself. That’s a lot of use out a single activated ability.The combined CMC of all the cards above is 7, which is usually the CMC of most game-warping, or even game-winning, cards in the Commander format. And while the big mana cards may still reign in the end, there is no reason to pass over cards on the small side of the CMC spectrum. In fact, given the right circumstances, these 1 mana cards can win you the game, whether sneakily or overtly. Building a great Commander deck is more about cards that help push your game plan along than it is about casting big, splashy spells.