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By: oraymw, Oraymw
Sep 18 2013 9:38am
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Welcome back to Ars Arcanum, the MTGO stats-based article series. We’ve got a new block on our hands, a brand new set, and a whole bunch of stuff to look at. The Theros spoiler is up at the mothership, and I’ve been hard at work crunching the numbers in order to talk about how the format will possibly shape up. First, I should talk about the basic premise. Creatures are the foundation of limited, and they have the biggest impact on the speed of the format and the playability of the non-creature cards. The first thing that we’ll look at is the speed and size of the creatures, and that will be our jumping off point for understanding the format.

I should mention that I’m taking a slightly different philosophical approach to these articles. The Dragon’s Maze article was very popular, and it definitely helped a lot of people get an idea of what they would be doing in a very complicated format. I’m proud of the work that I did on that article, but at the same time, there were a few serious problems with it, which helped me come to the realization that my methods were flawed in ways with which I was not comfortable. Because of that, I sat down and decided to figure out what things specifically I want to accomplish in these articles. First, I want to give an in depth discussion of the realities of the draft format. This means crunching a lot of numbers, and that was something that I was already doing. Second, I wanted to have thoughtful analysis of the data. This is where the articles struggled. In previous spoiler articles, I spent more energy on making accurate predictions than on analyzing the impact of certain sets of data. While I was very accurate in most of my predictions each season, the DGR season definitely showed the flaws in this kind of approach. Honestly, it feels awesome to correctly predict a format when everyone else is saying something different, but I don’t really think that is the best service to the community. Instead, I want to take the data and explore as many questions as I can about the format. This means that it will be up to the reader to determine what predictions to make from the analysis, so it definitely shoves more responsibility onto your shoulders, but it should make for a much more usable article. This does not mean that I will make no predictions; at the end of the article, I’ll make a brief list of predictions about the format, but those will mostly just be for fun, and the focus is going to be much heavier on the analysis. Let me know how you feel about this change.

Next, it is important for me to recap my methods. The most important concept that I use is something that I call rarity weight. Rarity weight is a value that is assigned to the different card rarities in order to help us understand how likely a card is to show up in a given draft. For example, Theros has 101 Commons, 80 Uncommons, 53 Rares, and 15 Mythic Rares. There are ten common slots in a given booster pack, which means that any common has a little less than a 10% chance of showing up in any booster. Each of the 8 players in the pack opens 3 packs, which means that any given common will be opened 2.376238 times in a given draft, on average. There are 80 uncommons, which is more than usual, and ends up giving us a .9 per draft rarity weight for uncommons. The rarity weights for rares and mythic rares are .396226 and .2 respectively.

Rarity weight is essential to any kind of numerical analysis of the set, because it weights the cards at the likelihood that they will actually end up in the pack. I should also say that while the article is geared more towards draft, the system actually rates each card equally, regardless of power level, which makes it a very good tool for thinking about sealed as well. It just means taking the numbers a little more literally. I disregard power level because as soon as I start introducing objective elements into the numbers, it is very easy for them to be skewed dramatically because of a poor assumption on my part, so I just won’t do that.

As a brief aside, I had talked about writing the second part of my Community Cup article, but since the Theros card list was spoiled a few days early, I decided to spend more time on this article, since the Community Cup article is a little less time sensitive. But don’t worry, that article will be coming soon.

Now that we’ve got introductions out of the way, let’s jump into the data.

Converted Mana Costs

Converted Mana Costs of Creatures in Theros

Converted Mana Cost is always a great place to start analyzing a format. This kind of CMC curve is exactly what I’ve come to assume is standard practice for Magic sets. A little later, I’ll put up a version of this chart from old sets, but the main thing we would notice is that it is very similar to AVR, RTR, and GTC. In fact, if I were to pick a mana cost distribution that best fits Theros, it would be Gatecrash. Both feature a heavy concentration of two and three drops, with a slightly heavier number of threes. Both have a fairly steady drop from 3 to 4 and 5. RTR, for example, had fewer five drops and a larger number of six drops, while AVR had fewer 2s and more 4s.

However, there are two small, but significant differences between the CMC charts for Gatecrash and Theros. These are that Theros has about 5 more 2 CMC cards than Gatecrash, and about 3.5 more 4 CMC creatures, while it has 4 fewer 1 CMC and a slightly lower number of 7 and 8 CMC creatures. This means two things; first, it means that two drops won’t be quite as competitive of a commodity as in Gatecrash, which probably bodes well for the format. It also has a higher density of 4 CMC creatures, instead of very expensive creatures. This means that there will be a little bit less competition for creatures in the middle slots, with just enough late cards coming around for those that want them. Overall, that probably means that Theros will be a little bit slower than Gatecrash, but these really are just slight differences, and not anything like what we see in a format like DGM, M14, M13, or M11.

Below, you’ll see a chart showing several draft formats over the past few years as well as a similar chart showing RTR, GTC, and DGM:

Converted Mana Cost of Creatures in RTR, M13, M12, M11, and AVR

Converted Mana Costs of Creature in DGM, GTC, and RTR

This just helps us put the CMC chart into a little bit better context. However, this really doesn’t tell the full story. There are three very important factors that make Theros an outlier when compared with the above stats. First is Bestow, which gives many creatures an alternate and higher casting cost. Second is Monstrosity, which provides a late game mana sink that can create huge creatures that can easily close out a game. Third is an emphasis on Auras, which you tend to want to cast on about the same kind of speed as creatures, though they are a little bit more restricted. With that in mind, I also put together another CMC chart that shows us the impact of all of these three factors.

Converted Mana Costs of Creatures, Bestow, Monstrosity, and On Curve in Theros

Let me explain this chart in a little bit more detail. The blue line is the chart that we saw above, which just shows the creature CMCs. The red line is what we get when we add both Bestow and Monstrosity costs into the mix. The green line shows us the CMC of on-curve, but non-creature spells. This is a little nebulous, but it basically means cards that aren’t removal or tricks, and focuses most heavily on Auras and Enchantments, though I did include expensive draw spells. The purple line is what we get when we put all of these different things together.

As you can see, this list is substantially different from the first list. There are a lot of important things to notice, so I want to take them piece by piece, and we’ll start by looking at the Bestow and Monstrosity effect. One of the things that I keep hearing from players is that Bestow and Monstrosity are slow mechanics. It isn’t hard to see why people would think that; they obviously have high costs. But, those people are ignoring a very important part about the mechanics, and you can see it clearly on this graph. We see that the line for creatures and for creatures + abilities exactly match each other up to 3, at which point they start to diverge. What these mechanics do is give you cards that you can cast in the early game, but that can still have a dramatic impact on the late game. Let’s take Leafcrown Dryad as a perfect example. In the vast majority of limited formats, Grizzly Bears is a great card to have in your deck. Unless the format is very slow, it’s just very important to make sure that you are able to play something that interacts with your opponent in the early game. In very fast formats, Bears are always relevant, but their problem comes in more balanced formats. You need them in the early game, but they become irrelevant in the late game. Meanwhile, you can’t load your deck up on expensive cards because you’ll play so many more games in the early game, but they become pretty important if the board stalls out. But, with Bestow and Monstrosity, you actually get the best of both worlds. Leafcrown Dryad can be a bear on turn two, so you get all the benefits of a tight curve, but it also works as an aura in the late game. This means that instead of drawing an irrelevant 2/2 as a topdeck, you’re giving your best creature +2/+2, which often has a dramatic impact on the board.

This is what that graph demonstrates. This format has a huge amount of late game manasinks that are built naturally into the format. This means that you are able to focus much more on early drops, since your late game will usually be covered anyway. This is one way in which abilities like Bestow and Monstrosity tend to speed up a format. There are three recent examples of this that demonstrate the point perfectly. The first is Flashback, which has a more obvious correlation. With Flashback, you are able to cast useful spells like Unsummon in the early game, but when you start to get into topdeck mode, you can sink your mana into a second use of the effect, such as with Silent Departure. Another example is the Werewolf mechanic from Innistrad. In the early game, you were very happy to have Villagers of Estwald come down as a 2/3 for 3. However, in the late game when you started to run out of cards, you could just not cast a spell, which would turn them into a 4/6 Howlpack of Estwald. This is actually very similar to what happens with Monstrosity; you effectively pay a large amount of mana (Monstrosity cost for monsters, not casting anything for Werewolves) to turn your early creature into a potent late game threat. Both of these mechanics contributed heavily to making Innistrad a very tempo oriented format. My mantra during triple Innistrad draft was always “This is Innistrad. Tempo is king.” The final example is the Level Up mechanic from Rise of the Eldrazi, such as what we see on Knight of Cliffhaven. It may seem like Level Up is a counter example, since Rise of the Eldrazi was such a slow format. But remember, the heavy Level Up deck was actually one of the few potent aggressive strategies in RoE. You could play Knight of Cliffhaven early on, get in a couple of damage while your opponent ramped, and once they played a wall, you leveled it up and continued the beatdown. Then, when you ran out of cards, you turned it into a Serra Angel to close out the game.

We’ll talk a little bit more about these mechanics later on in the article, but we also need to talk about Auras and Enchantments, as represented in the green line. The biggest factors in this list are the two cycles of 2  CMC auras, one cycle at common and the other at uncommon, with Fate Foretold as an example. (Yes, I know that the red common costs R). These change the CMC curve in really strange ways. You would think that they would drive the curve down, since they cost two mana, but the truth is that you want to play them on creatures that are already on the field. Now you’ll think that this will drive the curve up, but at the same time, they actively encourage you to play cheap creatures in order to take advantage of these auras. T1 Tormented Hero into T2 Scourgemark will probably be one of the defining opening sequences in the format. I honestly can’t predict fully how these cards will affect the format. What I can say is that they provide three important effects in creature based decks. First, they make it more rewarding to play early creatures, which also makes fast draws more punishing. Second, they give you more ways to use your mana efficiently in the midgame, by allowing you to play a bear and then drop an aura on another creature. This also seems to help aggressive decks. Finally, they let you topdeck a card that cycles and provides a possibly meaningful impact to a stalled board, which effectively gives aggressive decks more reach.

When we combine all of these numbers, we see a very fast curve that also has a lot of late game potential that is naturally built in. When I started thinking about this format, I started to get worried that it was going to be a lightning fast format like Zendikar, and if you are starting to feel like that, I can definitely appreciate the feeling. However, there is another huge factor that we need to discuss, and that is creature size.

Creature Size

Distribution of Power and Toughness for Creatures in Theros


Average Creature Stats in Theros







Average P/T Differential



In this chart, we see the number of creatures at each tier of power and toughness in Theros. In the following table, we see the average stats for creatures in Theros. These two charts paint a very different picture from what we saw in the CMC chart. We see a very heavy distribution of creatures at 2 power, while we see that toughness is spread out a lot more to the right. Most important, creatures in Theros have power that lags behind toughness at all the critical junctures. This means that it will often be difficult for Theros creatures to punch through defenders without help. But the most important factor is the average P/T differential.

Basically, this gives us an idea about how creatures will stack up against each other in combat in the format. Fast formats tend to have P/T differentials between -0.1 and +0.1. (Toughness is almost always greater than power). Average formats will tend to have between -0.15 and -0.35. For example, Gatecrash has -0.109, while RTR had -0.209. Theros has an average P/T differential of -0.505. This is a very strong indicator of a slow format. By looking at the average Power and Toughness, we actually get a pretty potent idea of what this means. In Theros, we will see a lot of creatures with 2 power facing off against creatures with 3 toughness. This leads to fewer attacks, which leads to board stalls, which slows down the format. The next two charts highlight this problem even more:

Average Power and Toughness of Creatures by Converted Mana Cost

Average Greatest Power and Toughness of Creatures by Land Drop

In the two charts above, Power is the line in blue, and Toughness is the line in blue. Let me explain them a little better. The first chart shows the average power and toughness of creatures according to their converted mana cost. For example, creatures with CMC 3 have 2.5 average toughness, while they have just under 2 average power. The most important thing is that toughness exceeds power at every CMC until we get to seven. The second chart shows the average power of the creature with the greatest power on the board vs. the average toughness of the creature with the greatest toughness on the board, according to land drop. Again, we clearly see that toughness outstrips power. If we just look at these stats, we would definitely be led to assume that Theros would end up being a slow format, because it’s naturally hard for people to attack.

This leads us to a dilemma. The converted mana cost analysis leads us to believe that the format will be very fast, while the creature size analysis leads us to believe that the format will be very slow. Honestly, I have no idea what this means exactly for the format, or what kind of strategy will be optimal. However, there is one more chart that we need to see in order to understand what is going on.

Average Power of Attackers with Auras, Bestow, or Monstrosity vs. Average Toughness of Defenders

Alright, this chart is very complicated. Let me explain a little bit about what I did, in order to help you understand what this chart means. Basically, I was looking at the size of the creatures, and I was trying to figure out how Auras, Heroic, Bestow, and Monstrosity change the attacking dynamic. All of these mechanics have some key things in common. First, they almost all increase the size of the creatures you have on board. Second, they all make it easier for you to attack. Finally, they all affect creatures that have already been on the board, which means that those creatures do not have summoning sickness. In other words, all four of those mechanics have haste. Let me explain a little better. Above, we saw that Theros will have a lot of 2 power creatures that are staring down 3 toughness defenders. This makes it hard to block. However, when I cast an Aura, target something with Heroic, or use Bestow or Monstrosity, I’m taking the creature I have on board, giving a bonus, and then going into combat. For bestow, this typically means changing my 2/2 into a 4/4, which means that I can easily attack. With Heroic, it typically means giving a +1/+1 counter, or preventing something from blocking. Again, this means that I get to attack. For Monstrosity, I’m typically giving something +3/+3, which makes it significantly bigger than anything on the board, which also means that I get to attack that turn.

What you see in the above chart is this effect. It shows the average power of an attacker after you use one of these effects as compared with the average toughness of a defender on that same turn. In this chart, power far outstrips toughness. In other words, these are tremendously fast mechanics. They are mechanics that make it much easier for you to attack on your turn. The best comparison I could find comes from Zendikar. In that format, landfall would turn your creatures from something small into something much bigger, typically a +2/+2 bonus (which compares quite nicely with Bestow). In other words, your creatures tended to be bigger on offense than on defense, which meant that you just always attacked past each other, like ships in the dark. The most common interaction in Zendikar was “Attacks?” “No blocks.” and it made the format into what was probably the fastest limited format ever.

So what we have is a set of mechanics and CMCs that put a tremendous pressure on the format to speed up. At the same time, we see a lot of pressure from creature size to slow the format down. Personally, I think this is masterful. It’s like you’ve got a car with one person pushing the gas and the other pulling the emergency brake. In a car, that leads to some of the most fun (and dangerous) driving maneuvers. Believe me, I live in a small town in the desert. I have done these things a lot.  I’m surprised that I’m still alive. This is what I imagine from Theros, and it makes it the hardest format that I’ve ever had to analyze. Honestly, I just don’t know what is going to happen. The result could be anything. I’ll make my prediction later on in the article, but keep in mind that this is frankly mind-boggling, and I don’t think anyone is going to have a handle on the format.


Now that we’ve covered the most important elements of Theros, I wanted to take just a moment to talk about Scry. This is a returning mechanic, as evidenced on Omenspeaker. When the Scry lands were spoiled, it quickly became evident that many players underestimate the power of Scry. Of course, those lands aren’t too relevant to limited, since they are rare, but it is definitely worth talking for a moment about the effect of scry.

In order to talk about scry, I took the data from all the ending turn charts I’ve done for each format, and I found what would be the average ending turns for the average set.

Average Set – Ending Turns

This really does model the average limited format pretty well. Most games are going to end between turns seven and nine. Now, the reason why this is important is because it helps us get a handle on the number of cards that a player will typically draw in a given game. In a seven turn game, the player will draw 14 cards, while in a nine turn game, the player will draw 16 cards. On average, in a typical match of limited, a player will see around 16.5 cards from their deck if they have no draw spells.

Now, in Theros, if we count the number of Scry cards, we’ll see that a normal deck will end up with about 4.5 cards with Scry on average. Typically one of these cards will have Scry 2. In order to figure out the average number of cards that we will see in the typical game, I plugged the numbers for these scry cards into the average ending turn graph. In the end, we see that a normal player with no draw spells will see 18.5 cards from their deck. This seems small, but it means seeing either one to two more land if that’s what you need, or one to two more spells if you need no more land. These kind of margins make a tremendous difference in a game of Magic. It seems like a Scry 1 isn’t doing much to your game, but it is the buildup of incidental Scry that has a large effect on the format.

There are two major ways that incidental scry changes things. First, it means that players will draw their mana more smoothly. This leads to more interaction in the early game. Second, it means that players are more likely to draw spells in the late game. Again, this leads to more interaction. Mainly, scry  makes players able to play more spells, which means that they have more decisions to make in any given game. I don’t know how this will affect Theros. If the format is fast, it means drawing more lands, hitting your early drops more often, and having tense tempo battles in the first few turns. Then, the players will be able to skip lands in the late game, which will make topdeck wars less random. However, if the format is slow, it means that players will be able to craft their draws a little more carefully to stay alive, and then draw to their bombs in the late game. Like I said, Theros could fall either way, but it is worth keeping in mind that Scry 1 is a lot more powerful than it appears, especially when it is spread throughout the set.


Now, we get to the part where I make predictions. I have been thinking a lot about the set, and I’ll just dive through a bunch of different predictions that are based on the things we’ve seen above. Remember, you really need to take this analysis and think about the cards on your own, but it can definitely help to go into the prerelease and your first draft with a few potential rules of thumb for understanding the format.

1.      Theros will be a very tempo-oriented format, similar in style to Innistrad, though perhaps a hair slower. I really doubt it is a really fast format, but I also don’t think it will be as slow as M14 or RoE. More importantly, it is the kind of format that is going to have dramatic tempo swings in the mid game, similarly to Innistrad.

2.      Bestow seems like a very good mechanic. Auras have a lot of natural upside, which is typically tempered by their drastic downside. However, with Bestow, most of that downside is negated. I know that I’ll be valuing these cards very highly.

3.      In a high tempo format with a lot of auras, bounce spells become much better. I would keep an eye on Voyage’s End, and I really think that it will be one of the over performing commons in the format.

4.      I think that blue is the best color in the format, and I’m torn between black and green for the second best color. However, both red and white could be quite surprising, because Heroic is such a difficult mechanic to evaluate. It feels like blue, black, and green are best equipped to deal with the highly variable tempo of the format. The lynchpin commons that I see defining these colors are Nimbus Naiad, Gray Merchant of Asphodel, and Leafcrown Dryad.

Those are all the predictions that I have to make right now. Hopefully this article was informative and helped you think a little bit more deeply about Theros as a format. I’m very excited to dig into the cards and start to get a better idea of how things will play out.

As always, you can follow me on twitter @oraymw for updates about articles. I’ve also put up a Tumblr account at http://oraymw.tumblr.com/ where I post links to my articles. You can go there and subscribe to the RSS feed, and then you’ll be able to get updates whenever a new article goes live. You can also check out my stream on twitch.tv/oraymw.

Finally, I encourage you to check out the podcast that I do with my buddy Zach Orts, which is called All in the Telling. In it, we look at stories from a professional standpoint in order to get a better understanding of why they are important to the human experience. But mostly, we just talk about what makes awesome stories awesome. http://allinthetelling.libsyn.com/

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Great article! by Ikoma_Aze at Wed, 09/18/2013 - 12:01
Ikoma_Aze's picture

A good analysis of the format, as usual. The dichotomy over the speed of the format is interesting, and I can understand why you're hedging your bets!

Not meant as a criticism, but I spotted two small typos, and wondered whether it's possible to get them fixed before even more people see the article (though no biggie, if not):
1) "In the two charts above, Power is the line in blue, and Toughness is the line in blue." (Last word should be red.)
2) In the paragraph below the penultimate graph "This makes it hard to block." (Last word should be attack, I think.)

Finally, I'm very interested in your thoughts about: "It feels like blue, black, and green are best equipped to deal with the highly variable tempo of the format."

Is that based mainly on the lynchpin commons? If you have anything further on this point, I'd love to hear it!
Just based on reading spoilers (ie no analysis) I'd ranked colours as White, Blue, Green, Black, Red... but honestly am more inclined to go with yours!

Thanks for the comments! I do by oraymw at Wed, 09/18/2013 - 15:01
oraymw's picture

Thanks for the comments!

I do try to make a solid prediction at the end of the article, but like I said, I don't want to make that the focus of the article. I have strong opinions on what I think will happen, but I think it is much more important for people to look at the data, think about things, and decide for themselves what the format will come to, because that will help them more in the long run.

As for typos, gaargghghah!!! I did a lot of proofing on this, and had help from someone else as well, but obviously you can't catch everything in an article of this size. But yes, #2 should say "hard to attack."

One of the other things I do when a format is out is I go through with some of my buddies, and we rate all of the commons in the set, and then we argue about who is the most right (always me ;). After rating the cards, it felt like blue, black, and green were the deepest colors, as well as getting some powerful commons. With that said, I definitely have my radar out on white, because it has the cards that were the most difficult for me to judge. I rated it a little lower, but I also tend to like white less than most people in general, so I'm not entirely sure how much that bias is affecting my judgment. Also, the value of white depends a lot on the speed of the format.

I do think red is weaker than the other colors, although red does have a few powerful spells.

In short, I think that your list is actually a lot closer to mine than it might seem, because white is the color I'm least sure about.

I would say one of the by xger at Wed, 09/18/2013 - 18:26
xger's picture

I would say one of the primary issues with white is that 3 of it's commons are vanilla creatures, and none exciting. Given how quickly a 2/2 is outmoded, only the 3/5 is ok but just nothing great.

Personally I'm not as keen on blue because it has no real removal. It has a few tempo plays so they will be good against an unprepared opponent but I feel as though some will be medicore to bad late game. If a tempo deck is strong though I can see blue being the best.

The 3/5 is also meant to be a by oraymw at Wed, 09/18/2013 - 19:55
oraymw's picture

The 3/5 is also meant to be a devotion enabler, because of the CC in the cost, but I agree that it seems to be lacking something.

As for blue lacking removal, I think it will be powerful to pair it up with black, for example, for what seems like a pretty sick control deck. Also, pairing up with green seems interesting since you've got a Prey Upon variant, or red, since you have a couple powerful removal spells there as well.

But I think that Voyage's End and Griptide are going to do enough work as removal to make blue pretty sweet. It's not hard removal, but I think that tempo removal will be more important anyway, since there is such a voltron feel to Bestow and Monstrous.

Bouncing will hurt bestow by xger at Thu, 09/19/2013 - 12:30
xger's picture

Bouncing will hurt bestow somewhat as it will separate the aura and creature but that won't always be back breaking. As for monstrous, bounce could be a bad thing as it could give them another chance to trigger. It's all situational, which is why I'm more hesitant before actually playing.