The Grixzard Cube is a cube dedicated to the best creature type in all of Magic...The Wizard!
The main thing to know going in (aside from Wizards being the only creature type), is that this is a three color cube featuring Blue, Black, and Red.
Why Grixis?
That's an easy question to answer, as all of the best Wizards are Grixis at heart! I had initially intended to do a 5C wizards cube, but the power level and quantity of wizards in both white and green was sorely lacking compared to the other three...so Grixis it is!
Another key aspect of this cube is that instants and sorceries make up 90% of the non-creature and non-land cards! This cube is designed to have just as many fights "on the stack" as on the battlefield. To that end, there are no planeswalkers and no enchantments, and only a handful of artifacts that care only about instants and sorceries.
This cube uses wizards, instants, and sorceries from all of Magic's vast history...from Alpha up to the current set. So while that fact positions this as a vintage cube, it is also purposefully unpowered. I'm a big proponent of "fair magic," but hopefully there are still enough powerfully degenerate things to do if that is your play style. More importantly, however, is that there are just as many answers available if you find yourself on the wrong end of that degeneracy.
I did have to make one small concession when building this cube, and that was to errata all Shamans and Warlokcs to be Wizards. Some of the best "wizards" in Rakdos are actually shamans and warlocks, so that change was initiated to help balance out the colors and include some of the better Rakdos creatures.
So while there are a few cards that care about one or two of the creature types, for this cube and the wizard tribal cards within, all shamans and warlocks are to be considered wizards. Furthermore, any card that specifically calls out shamans, will also affect wizards and warlocks as well.
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