When considering cards for a cube, many people look first to those that perform successfully in other formats. Cards that are good in cubes have typically had success in other formats. Spectral Procession has enabled countless Standard and Extended token-based strategies and Vampire Nighthawk was arguably the best card in Zendikar limited. Does this mean that a card's success in a other formats is proportional to its success in cube? Not really. One of the most valuable cube design skills is an understanding of context. Unfortunately, simply seeing that a card has been successful and sticking it in your cube is a mistake if you do not also understand its strengths and weaknesses in relation to the card pool represented by your cube.

When using other formats as a tool for cube card evaluation, keeping these 3 factors in mind is key:

1. Does the card in question perform its role well when considered in the context of your cube?
2. How well does it perform the task when compared to other cards that perform the same/similar task?
3. How well does it compare to other cards at the same casting cost?

For example, let's look at Crypt Rats. It's a windmill-slammingly awesome card and there are few cards that I'd take over it in a commons cube because of its ability to "wrath" the board at instant speed, but it isn't anywhere near making the cut in my powered cube. However, Duress, a card that is weaker than Crypt Rats in the context of my common cube, ends up being stronger than Crypt Rats in my powered cube. Why? There are much fewer mass-removal effects at common rarity. The only ones that I'm running in my commons cube are:

Crypt Rats, Pestilence, Evincar's Justice, Martyr of Ashes, Festercreep

However, when Crypt Rats leaves the world of commons, suddenly its competition gets a lot stiffer. Its mass-removal effect may be a strong effect in common cubes, but in powered cubes, there are much better options like Damnation (at 4 mana) and Decree of Pain (at its 5 mana cycling cost.) Crypt Rats also isn't very efficient when compared to the other cubeworthy 3 mana creatures like Bane of the Living, Bone Shredder, Vampire Nighthawk and Hypnotic Specter (as well as others like Undead Gladiator which aren't quite good enough.) Crypt Rats compares favorably to common cubeworthy cards like Chittering Rats, Skittering Horror and Phyrexian Rager, but to vampires with lifelink, deathtouch and flying? Not so much.

Yet, when Duress makes the leap from commons to powered, while its competition obviously gets tighter (with cards like Thoughtseize and Mind Twist) – Duress' effect still compares favorably to not only the other cards at 1 black mana, but other discard effects in the format as well. Sure, it's not as strong as cards like Mind Twist, but Duress' overall effect at {B} is still extremely efficient and therefore good enough to make it into a powered cube.

I'll illustrate this further with other effects. I find that many commons cubes initially make the mistake of simply porting over powerful common cards from limited formats without understanding their context, such using as many pingers, tappers, damage preventers, growth effects and evasive creatures as they can in their lists with little regards to their efficiency solely because said cards were good in their respective formats.

In Lorwyn limited, paying 4 mana for a Neck Snap or 5 mana for a Weed Strangle was perfectly fine and taking those 2 cards highly wasn't unheard of, as these are pretty standard costs for "limited-only" removal spells. Even if the format had more efficient removal effects at common (Nameless Inversion at {1}{B}) – removal effects are scarce enough so that these effects are valued highly. Planeshift's Death Bomb was a nod to this; a litmus test to see how much would be paid for a removal effect. The scarcity of removal in limited formats also gave creatures such as tappers and pingers a much longer lifespan and, thus, they're able to make a much longer impact on a board state in a normal limited environment than they would make in a cube.

The context for cubes is much different as the bar is much higher for effects like removal (even at commons level) than in a limited environment due to the available options being more plentiful and more efficient. Thus, something like Neck Snap isn't good enough for a commons cube because it's an inefficient removal spell (compared to effects like Arrest and Temporal Isolation) and it's significantly worse than other effects at 4 mana (Guardian of the Guildpact, Cenn's Enlistment.)

Giant Growth effects are also generally strong in limited environments due to the high amounts of creature combat and damage-based removal. Like with removal effects, they're also picked pretty highly (although nowhere near as highly as removal) but the same rule applies in that, while something like Untamed Might may be awesome in Scars of Mirrodin draft, but this is irrelevant since it isn't anywhere near as efficient as cards like Groundswell and Vines of Vastwood. Untamed Might's ability to potentially provide a larger boost to a creature is mostly irrelevant and its inefficiency makes it a suboptimal commons cube choice, even if the card is a great card in sealed and draft.

Therefore, the fact that it's an extremely good card in normal limited formats is irrelevant and shows that a card's strength in limited isn't proportionate to how well it performs in cube. As mentioned earlier with Vampire Nighthawk, there's a correlation between performing well in other formats and performing well in a cube, but it doesn't imply causation and any statistician worth his or her salt knows that there's a world of difference between the two.

I've talked about limited and its contexts, but what about constructed?

Generally strong cards that require little support such as Siege-Gang Commander don't lose much value when going from their respective Constructed formats to cube and therefore do very well there. This is because even without explicit support, cards like Siege-Gang Commander are still extremely good card due to it creating 5 power, spread across 4 bodies (each of which can be turned into 2 mana shocks) which compares very favorably to other red 5-mana creatures in cube. Granted, when the commander can be retrieved via Goblin Matron in Goblin decks, it's even better, but even without such explicit support, cards like Siege-Gang Commander are amazing on their own merits.

Other cards, like Primeval Titan suffer from the inability to reliably make a deck that can utilize what made the card so good in Constructed. Primeval Titan has been deemed the "best titan in Standard" because it can search for lands like Valakut, the Molten Pinnacle and "Eldrazi" lands such as Eye of Ugin and Eldrazi Temple. Primeval Titan can perform a similar role in that it can search for lands such as Maze of Ith and Library of Alexandria and thus, people use it in their cubes, but this is a mistake. While Primeval Titan has useful targets in cube, it does not have enough to warrant its inclusion, since there are few opportunities to make Primeval Titan‘s search ability worth using.

While you can "live the dream" and draft a Maze of Ith to stop a troublesome creature, how often is that going to happen? Most of the time, its targets (basic lands or mostly worthless mana fixing lands, lands such as Library of Alexandria with a smaller hand) lose a lot of value when the titan gets cast. Its body also doesn't compare favorably to other 6 mana options, especially ones like Wurmcoil Engine, Mold Shambler and even arguable "virtual" 6 mana creatures like Thornling. While cards like Mistbind Clique and Goblin Ringleader may look very different than the green titan, they suffer similar fates, since the critical mass of creatures required to support these cards simply doesn't exist in a cube, making them unplayable. You can make an awesome deck with 30 goblins in Legacy, but there aren't anywhere near that amount of cubeworthy goblins.

This doesn't mean that you should be a total pessimist, but when evaluating cards that rely on other cards to be powerful, you need to be realistic in evaluation. For example, I had initial doubts about Stoneforge Mystic because I thought that there wouldn't be enough targets for it as 1 target for Stoneforge Mystic is awful. However, I found that the mystic was able to be drafted with at least 2 equipment many times, showing that she had enough support in my cube to be a strong card in my cube.

With cards like Fastbond, it's another story. While the card may look impressive since it can "make your lands into moxen" – the problem is that, realistically, the card won't perform like that most of the time because it's a singleton card. Someone can "live the dream" and have a play like "forest, Fastbond, bounceland, land, land, Mutavault, 3-drop, go" but for the most part, this won't resemble its average use at all.

Other cards work well because they prey on aspects of a format. A friend made a commons/uncommons cube and used Ricochet Trap. He's a big Vintage player and the card is solid in a format like Vintage, where the card can redirect cards like Ancestral Recall, but it isn't very useful in a cube because of the small amount of blue instants to affect and its inefficiency when it is cast without the "trap" cost. Oxidda Scrapmelter is a great card in Scars of Mirrodin limited because there are so many artifacts, but how would it perform in M11 draft? It'd still be a fine card due to the fact that Hill Giants are the benchmark for decent draft creatures, but would it wouldn't be valued as highly as it is in Scars of Mirrodin because it can't prey on the prevalence of artifacts like it could in its native format.

I hope that this has helped you understand the role of context when evaluating cards for your cube. If you've enjoyed my words on cube drafting, I post similar content on my Wordpress blog and on Twitter, at @UsmanTheRad.

Thank you for reading, cheers!