I have been giving cards a generic 0-5 rating on a single scale of how good they are but I feel this doesn't really paint an accurate picture of the card at all. I am going to slowly go through all the cube card reviews and give them two different additional ratings, still 0-5 but to represent different strengths of the card. The main rating will remain but as a reflection of the component qualities, I will also review some of those main ratings which are a little off, either due to changes brought on with new cards or simply a poor initial scoring. The two categories will be "power" and "support" however I could break these down further but it would be getting a little convoluted, which for an already arbitrary rating is rather over the top.
This relates to a few aspects of the card, which to make things difficult are not always aligned. This category will relate to the possible synergies the card in question has with other cube mainstays and strategies. It will also refer to what proportion of archetypes that will consider playing it. A card with lots of synergy that is viable in a variety of archetypes will score very highly in this category. Also factored into this ranking will be a few things that typically deter from a card. The first is how awkward the card is to include in decks, these are synergy dependencies that mean the card is pretty useless on its own. A great example would be Stoneforge Mystic that requires you to play equipment. Other cards are more subtle and simply have a slight nombo with one or two cards such as Skullclamp and Samurai of the Pale Curtain, you can still usually play them both but they will be marginally weaker if you do. Phyrexian Obliterator is another card that would be marked down in this area as quad black makes it a very awkward card to include. A card will typically be marked up a bit in the support category if the cards it has synergy with are also very highly rated cards, likewise if it has synergy dependencies with weaker cards it will be marked down further. Narrower cards will typically score quite low on support rating because they tend to have very few supporting archetypes and even when they do have great synergy with some cards they will also tend to be narrow ones themselves.
Every single deck that can play this card should want to and most archetypes should be able to play it, it shouldn't require other cards to make it good yet it should itself make many other cards much better. An obvious example of this is Black Lotus.
Still desirable in every deck that can play it but more restricted in which those are, typically this is the cream of the gold cards such as Fire/Ice and Vindicate. They should also remain top quality themselves without supporting synergic cards while improving those they are with. Another card that would get this rating for support but would be far lower on the power scale is Chromatic Star which is viable in every deck and has some fantastic synergy however none that could be called broken hence not getting the top marks.
This is level of card is usually a contender for a deck of the right colours and while not making every list it probably could have done and not looked too out of place. It may be at its best with some specific cards but is still top quality without them and should be able to offer some neat interactions with other decent spells. Jace, the Mind Sculptor is a card that fits the bill for this rating.
This level of card tends to be archetypal mainstays but not colour mainstays. They should not depend on other cards to be good but don't always require great synergy with others so long as they are in enough decks. Goblin Guide is a card that would be given a 3.5 score.
The range of cards starts to slip away from being mainstays in archetypes and while still being strong in at least one will not always make the final cut. Typically these kinds of cards have both some synergy with other cards and some weak interactions as well. Dryad Militant is the first example card that springs to mind for this range.
These cards are now starting to be rather narrow and while still often having some very good synergies it is with a few cards that go in just one or two archetypes and those other cards are themselves nothing to get excited about. Cranial Plating probably falls in this range on the support category.
These cards are close to unplayable without support from other cards and are only even kicking around to perform a single specific role. They will be incredibly narrow and often have more negative synergies that they have positive ones. Mana Severance comes to mind as a card that would fall in this range.
I dislike the concept of thinking about a magic card in a vacuum, not only is it impossible it yields no useful information. A better way to view the raw power of a card rather than how it might fit into an environment would be some form of top deck magic that took into account mana costs in some way. It is a much more mechanical method of analysis that breaks down the component parts of the card and values them against the costs of the card. To do this however you need to know what things are worth roughly, how much damage to you get per mana, what power and toughness are dorks of this cost etc? You can only ever assess the power of a card by comparison to others but what you can do, as with many people unintentionally, is not consider any interactions at all. Ultimately power is the primary statistic for a card and will be somewhat of a cap on any overall rating it can be given. Having said this the overall rating of a card will not be weighted towards the power average of the component rankings, rather the weighting will be proportionally higher on the lower of the two components whichever that might be. The lower they get the greater their weighting which is just another way to say a card is always held back by its weakest attribute more than it may be carried by a strong one.
A totally unreasonable level of power that shouldn't have been printed in all likelihood. What the card does for its mana cost should be vastly above the curve. Typically later printed cards doing similar things will be obvious multiples better, say Black Lotus to Lotus Petal. In the case of creatures it is often the other way round that the newer one is multiples better than the old although none quite deserve the 5.0 rating of power quite yet.
This level of power should still immediately raise an eyebrow, even the relatively inexperienced player should be able to clearly see this card is a whole lot more card than the others floating around. As it is a relative scale and the most powerful cards by some margin came at the dawn of magic only the few bomb cards that come very couple of sets get this score such as Snapcaster Mage. I would be highly surprised to see a 5.0 for power get printed.
These are the staple power cards of which most sets have a few to offer the cube. These cards are powerful enough to have decks build to include them and shift the meta to accommodate themselves a bit better thus automatically upping their support rating a little. Many staple and familiar cards would get this score such as Tarmogoyf.
These are the solid cards that are all comfortably above the average cube power level but are all looking a lot fairer such as Inqusition of Kozilek and Remand.
Still above the curve, even for the cube but only just and typically not in an overly exciting way. Loyal Cathar is a good example
In this range we tend to only find cards still keeping an A cube slot when they have a much higher score on the support side of things meaning they are widely played and work well with other good cards. There are of course many cards of this power level and comparable support ratings filling out the B and C cube.
Very low powered cards that can be nearly as weak as some of the weakest cards ever printed in magic such as Stinkweed Imp, these will only ever be in any part of the cube should they have specific purposes as they simply don't cut it in terms of power with other cube cards
The Composite Ranking
I have spoken about how I will combine the two ratings for power and support to get an overall "how good this card is in cube" rating.
Only cards with absurd power levels will be able to get this score and even then only those that are widely playable. Because of the power needed to get such a rating I have banned every 5.0 ranked card as they are all a bit random while being highly game changing.
The cream of the cube, the most powerful and most played cards that form the backbone of the core archetypes. These will all have a minimum power of 4.0 and usually higher.
Not too far removed from the 4.5s, either marginally less well suited to the cube or just a bit less powerful but otherwise all still top cards of high power.
These cards are the cube staples and will either be fairly generic high powered cards or archetypal mainstays .
Above average cube cards that tend to fill in rather than make up the core of a deck.
At this rating cards are starting to become more niche or of below average power and are often flitting back and forth from the A cube to the B cube.
This is the composite rating at which I tend to start culling from the A cube. Either they are very powerful cards that simply have no decks that want to play them or they are core cards but from tier 1.5 or weaker decks. Lots of combo pieces fall into this category.
These cards are low powered cards that don't have homes yet or if they do they are in bad decks. Most of the C cube is cards I would rate at 1.0 or lower.
This is the bar for a card to be considered for a place somewhere in my extended cube. If I can think of some application it may one day be useful but is otherwise low power and unplayable in any present archetype it would get this sort of a rating. Almost all of the cards 0.0 - 0.5 never actually see play and just collect dust but it is still useful to have set aside. There are many cards that are worse than a 0.0 on my scale but they are all unplayable in cube so a relative rating for them is irrelevant in this situation.
Anyone who reads my initial set reviews will be aware that I rate some cards with numbers 0 to 5, others with B or C cube and completely ignore others. Those I ignore are those with lower than 0.0 rating. Those with a 0-2 numerical rating are likely not going to stay in the A cube but have been given more thought to, will be more relevant within a cube and are more obvious as to how they will perform in one. Those that I just slam a B or C cube rating on are generally less clear or less relevant and so can only be given or only warrant respectively an approximate rating. Typically cards with the approximate ratings are not ones I will go out of my way to test unless I state it in the review.