Cube Power Level: A User’s Guide

One of the most fundamental design choices a cube designer makes is that of cube power level. But it can be difficult to draw connections between the abstract concept of “power level” and its ramifications on a format. I’ll define power level, discuss the design tools we have to change power level, and suggest considerations for choosing your power level.

Approaches to power level in official Magic formats like Standard or Booster Draft may consider the speed of a format, or the rate of format staples relative to Magic’s history. For Cubes, which are designer formats with unique metagames and a lack of reliable statistics, defining power level is nontrivial; we can’t rely on easy heuristics.

A card’s viability in a cube will depend, not on its Constructed success, but on every other card in that cube. Even the mighty Sol Ring’s playability in cube is attenuated if the rest of the cube contains no generic mana costs. In this context, Sol Ring is the worst card in the cube! But it is still difficult to talk concretely about the overall power level of any given environment.

To anchor our discussion in practical Cube design, I use a thought experiment: if we assign a supercomputer¹ a set of design goals and restrictions, and then ask it to rank every possible Cube (i.e., every possible combination of 360 Magic cards²) by power level tiers, it would look something like this:

There are about 10⁷⁸⁹ ways to combine the ~21,000 extant Magic cards into a 360 cube — more possibilities than there are atoms in the universe, by a lot. The bulk of those combinations are low-power, because a random Magic card is most likely to be out-moded, old, draft chaff, or all of the above.³ The groups of mutually playable cards that lead to this “might-as-well-be-random” power level are innumerable, and thus these cubes form the wide base of the pyramid.

As we move farther up from the base, we get fewer and fewer combinations of cards which yield the same overall power level — for example, you can use your fingers and toes to tally up the number of red burn spells defensibly interchangeable with Lightning Strike, which is a number obviously greater than 1, but much smaller than the number of Red removal spells which round down to Open Fire.

And finally, the apex of the pyramid is the “most powerful group of Magic cards ever,” which our supercomputer determined for a particular set of design goals and restrictions. If you change that cube by even a single card, you’ll be lowering the power level of the cube, meaning that there is only one set of interchangeable or mutually playable cards at that local peak.⁴

There are, of course, other peaks, corresponding to other sets of design goals and cube architectures — for example, a Vintage cube that supports Splinter Twin and Channel combos will have a different peak than a cube that has identical restrictions, but does not support combo. Because the power of individual cards depends on context, the cube itself will have different max-power configurations based on the starting point. In this way, power level is like a mountain range, and each peak is only a local maximum of power level.

Regardless of design goals or cube architecture, the higher a cube’s power level, the smaller the number of interchangeable, mutually playable cards for that cube. This restriction of designer agency as cube power level increases is a basis for actionable design “knobs” we can tune to our liking.

Power outliers — cards that are extremely strong in their context — are a design knob with outsized effects on mutual playability (and thereby power level). We know from Constructed formats that an environment’s play patterns are often defined by its highest power outliers. Standard, for example, warps around outliers like overtuned mythics, pushed synergies, or singularly efficient threats, crowding out metagame choices incapable of competing at that level. Sometimes, bans occur to increase the playability of alternatives; indeed, bans are only effective because of the massive impact that power outliers have on a format’s metagame.

Other power outliers may not be banned, but still go on to define their Standard format. Similar analogies can be drawn to outliers in Modern, Legacy , or even Vintage. Power outliers are also important in Cube contexts due to the draft portion of Cube play — outliers will be drafted earlier, seen as draft signals more often, and maindecked more consistently. In short, power outliers are a cube’s strategic backbone.

Certain groups of cards can also be a design knob with a strong effect on power level, even if the individual cards aren’t outliers. For example, low mana value cards have low opportunity cost, and they tend to make positive tempo exchanges versus higher-MV ones, making those expensive cards less playable. This restriction of mutual playability increases power level. This is especially true for removal spells. Final Death is tempo-positive against Ancient Brontodon but not Baneslayer Angel; Doom Blade is tempo-positive against Baneslayer Angel but not Elvish Mystic.

In draft and deckbuilding, cards with low risk can make more volatile cards less playable: Shock can be cast any time its owner has priority, but Prey Upon isn’t guaranteed to have two legal targets, so a win-motivated drafter choosing between the two will tend to prioritize Shock. Modal cards also offer a way to mitigate risk. All else equal, MDFCs, cards with Kicker, Charms, cyclers, and the like will be valued higher than cards with less flexibility . This is especially true in formats like singleton Cube Draft, which are already high-variance by nature.

Even entire strategies can be used as a design knob to tune mutual playability, the most famous of which is the prototypical aggro deck. The small aggressive creatures which form these decks’ backbones are obviously weaker than slower cards in a head-to-head. But in aggregate, high-damage-rate creatures like Jackal Pup and Goblin Guide will tend to speed up the format, which gives high-MV cards more risk in the metagame, which decreases the number of viable high-MV cards in that format, which increases power level.

Though design knobs will allow us to tune a cube to any target power level, it can be difficult to pick that target in the first place. My design experience has revealed several trends that different power levels create in cubes. As with all aspects of Cube design, no single power level is “correct” or “superior”, and there are advantages to a variety of design choices.

• Easier (and cheaper) to find combinations of mutually playable cards
• Relatively easy to ensure pet cards or favorite archetypes will be prominent features of the format
• A majority of newly released cards will easily integrate into the environment, permitting a quicker update cycle for highly active playgroups
• Low-power cubes can easily resemble slower formats like Retail Limited, Standard, or kitchen-table casual that place a relative emphasis on gameplay skills like card advantage and threat evaluation

• Easier to conceptualize high power formats — since the power outliers of Magic’s history are usually well-known to Cube designers, they can harness Constructed heuristics and knowledge
• To build high-power on a budget, designers can simply decrease the average MV of their interactive tools (discard, counterspells, removal), which will invalidate more expensive threats without affecting cheaper threats (in dollars and mana)
• A slower pace of updates is possible, since fewer cards from each new Magic release will be mutually playable with the existing cube
• High-power formats can easily resemble fast formats like Legacy or Modern that place a relative emphasis on gameplay skills like tempo and sequencing

• Making incremental, like-for-like swaps to a Cube is a good way to hone in on a desired power level, because those small changes are unlikely to lead to big shifts in mutual playability.
• Conversely, bigger updates like slowing a format’s removal or removing a prominent archetype will help designers jump to a new context entirely in the power level landscape. The new context will make it more obvious when the mutual playability of cards change, but these bigger updates take more energy.

Regardless of your design goals, power level is an exceedingly complex, abstract idea that is tough to apply. Envisioning power level as a measure of mutual playability opens up a wealth of design tools. Happy cubing!