In every review of every gold card, I feel like I drone on about their reduced playability for cube and how it’s a problem. As a time saving tool, I am going to cover why that’s the case in this article and simply refer to it in future. With another gold heavy Ravnica set due, now seems like the pertinent time for this!
In terms of how good a card is generally, you are looking at a couple of things – First and foremost, how powerful the card is, which is determined by what it does and how much it costs. You just compare it to other cards you know the power level of and triangulate a power level for it, based on that. Fairly straight forward.... when you accurately understand the power level of all the cards *and* how much each component element of a card should cost *and* how each of those things scales with all other effects!
Next up, you look at the context of the card, you consider it for standard/modern/whatever and look at which decks it might fit in, or what cards pair well with it. Some cards are so powerful that they will form new archetypes around them, while others might be relatively weak but fit into a gap in an existing and powerful deck. The context for where you are aiming to use a card is a modifier on the power level you "triangulated" in your initial appraisal of the card. It can make it better or worse and it can be a minor change, or a big one. It requires a experience and understanding of the meta in question to be able to take into account usefully.
For most of magic that’s you done for card evaluation, but for cube there is another step. In cube, you are essentially designing a format. You are not just doing the deck building stage, but also building the format prior to that within which those decks are built. This means it all gets a lot more complicated. For one, you have control over the context. This means you have near-infinite variation and scope to build a framework from. You can make good cards poor and bad cards viable. You are not building a deck but you are building a limited format which contains the potential for as many or as few decks as you choose. Building good decks has rules like sensible curves and good land to spell ratios, and building draft formats also have these kinds of elements. There are many different interpretations of cube and many different parameters people build to. A long time ago, I was almost entirely driven by card power levels and I would let that determine the meta, but over time I have used my control over the meta and my understanding of that to craft a "better" format.
My interpretation of "better", in this case, is a blend of good diversity in decks, minimizing random elements, and maximizing choice. These things are what I think lead to good games of magic. Ultimately, that is what these games are for – fun! - and that is how I like to play my magic, and hence that is how I tailor my cube. I build a cube in a way that I would argue maximizes my fun. I am aiming at using the best cards, sure, but now my overriding principle is to create the best format. A good cube card for me has a good blend of power and playability. The former effects the latter, but the latter is the more important attribute for drafting cube inclusion. Playability is what most helps to increase the choice in draft and reduce the random element.
So, what does all this have to do with gold cards? In order to maximize choice and minimize random factors, you want as high a number of playables as possible in any given booster. That is basically the answer. Gold cards are inherently less playable in a limited setting than cards of fewer colours, and that means they reduce options simply by being there.
I have done this numerical look at it before at least once in this blog, but I have no idea where, so I’ll do it again here where it should be. There are 33 possible colour combinations in magic (if you include colourless). A colourless card can be played in all 33 of those. A card of single colour can be played in 16 of the 33 total. A two colour card, however, can only be played in 8 of the 33 possibilities. A three colour card can do 4 out of the 33. As we can clearly see, adding a colour halves the playability of a card, however it actually does more damage than that. With dual lands being contested and requiring picking, you find that even with good fixing options that people stick to relatively few colours. Two colours is the most common, with mono probably just edging out three colour decks in draft (in sealed where you don't have to use picks on fixing you find way more three plus colour decks). With that in mind, adding in colours is even more harmful to the playability of a card, as you remove the more commonly seen options first when you increase the colours.
The problem with cube design and this principle is that nothing is linear. Gold cards are absolutely not twice the power of mono coloured cards, which the maths would point towards as being the requirement for cube inclusion. This is the point at which it all gets sufficiently complex that math is no longer that useful. For example, it is nice to have a smattering of gold cards in the drafting cube for the case of colour signalling. You can use the wheeling of a solid gold card as a good indication that that pairing is open. Lands are too easily picked up speculatively for them to be a reliable test of availability of a colour pairings.
If you are just looking to maximize the playability of the cards in your cube, you should look to keep gold cards lean. If you were purely adding in cards to your cube based on power, you would have more gold cards than non-gold ones however. There is a weird tipping point of power level on gold cards where they start to warp the meta, and this is the point at which I try and include gold cards from. You expect your gold cards to be a little better than mono equivalents, as that is how they are designed. Most of those ‘slightly better’ cards see too little play to merit slots in cube. A step above this in power and you are usually at cards that see play in most to all decks of their colours. These are fine cube inclusions. They offer mild incentives towards going into a colour pairing, generally see enough play to merit their inclusion and obviously they pack plenty of power. The issue with these kinds of cards is that they need the colour pairing in question to be good to begin with. If you follow this power level guide for including gold cards, you will find that most of the gold cards in the weaker colour pairings see little play. If you go yet another step up in power, you reach a point where the meta warps around the gold card sufficiently that it sees enough play. It is almost as if the measure of power on gold cards is a logarithmic scale once you are above the power curve. You don't need your gold cards to be twice the power of the non-gold ones, just more powerful enough that people are willing to build for them, towards them or around them.
This is the main difficulty in reviewing and adding gold cards to the cube. I know they need to be more than just a bit above the curve, but beyond that it is mostly an educated guess as to how much above the curve a gold card needs to be before it sufficiently makes up for it's inherent lack of playability to be cube-worthy. The line is very fine and moves continually with all the changing contexts and new cards. What seem like tiny fluctuations in power can be the difference between a bomb that sees no play and a bomb that is meta defining.
Lightning Helix is a great example of a card that is a significant amount above the curve but not enough to get any extra play. It goes in all the Boros decks, basically, but there are not enough of those drafted for Helix to see more play than any of Searing Spear, Lightning Strike or Incinerate. Terminate is subtly different to Helix, as it is in a color pairing that sees a lot of play but it doesn't see more play than cards like Go for the Throat, as it isn't ‘better’ enough. The Scarab God is a great example of a card that is so powerful that it does warp the meta around it. You go out of your way to play it, because it is so dominant in a game. There are loads of other black or blue top end cards with loads of power and game ending potential, but The Scarab God is sufficiently more powerful than those cards that it does see more play than they do.
So that is the trouble with gold cards. They are narrower by nature, which is a bigger problem than usual as a format designer rather than a deck builder. That issue poses questions about where you draw the line and what balances you want to achieve in your cube. It is an issue that limits your design scope somewhat, in that you will wind up with a pretty bad cube if you just go nuts on adding in gold things. The second issue is with evaluating them to begin with. Just knowing cards need to be at least two steps above the curve in power isn't a huge help. With no good way to tell exactly were a card sits in power and how much that specific card needs in terms of extra power, your only real recourse for adding gold cards in to the cube is to test them. Either you wait for the community to test things and follow their lead once enough time has passed, or you have to do it yourself in a long and manual process. This is what I do, but I still miss a bunch. I can only fit in so many gold cards at any given time without hurting the experience, and so I have limited capacity to test out gold cards manually. It has happened before that a card didn't get attention, for whatever reason, while it was in the cube for testing and I cut it before it had its chance to prove itself.
Lastly, as a disclaimer, I am only talking about gold cards that require you to have two colours of mana to be anything other than a blank. Vindicate is useless unless you have your black and your white mana handy and is the kind of gold card I am discussing in this article. There are lots of cards that are technically gold, or have properties like gold cards, but that are actually far more playable in a general sense due to their partial functionality or flexibility. Lingering Souls and Fire / Ice are great examples of these partial gold cards. Then all the hybrid cards, such as Kitchen Finks, also fall under this umbrella as do things like Shalai, Voice of Plenty, and they are typically even more playable.