Last week's Modern metagame update indicated that Modern is quite diverse. The online metagame had 84 distinct decks while the paper metagame had 108. Modern is a huge format where almost anything can win. However, I'm often left wondering how meaningful that statement actually is, and judging by general online discourse surrounding Modern, I'm not alone. So, I've decided to follow up on that update and investigate from a new axis: Modern's strategic diversity.

Pop Quiz Time

Consider the following three-turn opening sequence:

What deck is this? Archetype? Colors? Another example:

Again, which deck? And finally:

Take a moment to lock in your answers before proceeding to the next section by leaving them in the comments!

Answer Sheet

It might seem obvious which decks I'm describing, but of course, I've set a trap. Which the observant and/or genre-savvy probably noticed. However, that's also a trap. You'll have to trust me about which decks I was looking at when making that puzzle; if you don't, I'm willing to swear on whichever holy thing it will take (as long as it's not dangerous and/or icky).

1. This is not UR Murktide. It is actually this Temur Combo Breach list by Takuto Tsuboi.
2. If you answered Indomitable Creativity, your answer is technically correct, but insufficient. You must specify the color combination for full points. In this case it was this Temur Creativity deck with a black splash, piloted by scipios.
3. This deck is 4-Color Bring to Light deck by OZ_Senpai.

Did anyone get them all right? Did anyone get any of the decks right? Probably not, and that's my point. There are a vast number of decks that play extremely similarly despite being demonstrably different decks. This begs the question of how strategically diverse Modern actually is.

Valuing Diversity

While there is no way to know how many decks a format can support, or even should support, players will agree that more is preferable to less. The more decks that are playable and, equally importantly, competitive, the better.

This idea underpins my yearly State of Modern article. I mentioned it then, but Modern's competitive diversity is suffering. For better or worse, the best decks take advantage of Modern Horizons 2 more than other decks. As my thought experiment shows, this means that lots of decks feel extremely similar because they're all playing the same cards.

This translates into many games feeling dismayingly similar, at least initially. I deliberately stopped on turn three because on turn four, each deck is going to start playing spells that help identify and differentiate it from the pack. However, even then, there are so many decks with similar plays that it is plausible to play through an entire match without even a highly informed player figuring out exactly what deck they just faced. This begs the question: how much of Modern's "diversity" is really just the same strategies masquerading as different decks?

Quantifying Diversity

In order to reexamine the metagame with an eye to its strategic diversity, I'll need to combine similar strategies. There is necessarily some subjectivity in doing this, but there's also a lot of very obvious decks to combine. Grouping the Creativity decks is easy, as they all share the same general strategy and most of the same cards. Their differences are in the details. Same thing with the Crashing Footfalls decks. Meanwhile, and despite MTGGoldfish's laziness, Domain Zoo is a distinctly different deck from Counter Cat, the former being a midrange beatdown deck and the latter a tempo deck.

Then, there are the Omnath decks. Does having Omnath in the deck constitute an Omnath deck, or does that distincton require more? I decided that The Omnath Deck is a midrange deck with Wrenn and Six and lots of removal, allowing me to sweep together all the midrange and control variants into one deck. However, the Glimpse of Tomorrow combo deck, as well as Copycat, remained separate, since they're sufficiently distinct from other Omnath decks and each other. Similarly, there were many different Storm decks in the data that remained separate because they play very differently.

For UR Murktide and similar decks, I decided that the mix of Channeler, Ragavan, Bauble, Iteration, and Heat formed the core of the deck. All decks that shared that core were grouped together under the Izzet Aggregate banner, regardless of whatever ancillary strategy was bolted to that core. This meant all the tempo, midrange, and combo decks together, since they all play the same early game.

The MTGO Aggregated Metagame

After going through all my data for February and aggregating all the similar strategies, I was actually surprised at how few aggregated decks ended up on my tier lists. The only one that didn't make the list was the aggregate Goryo's Vengeance that was getting some play online. However, the overall diversity of both mediums was greatly affected, and the stats changed considerably.

I am only working with the population statistics, as that's what's relevant for discussions on strategic diversity. For MTGO, the total unique decks fell from 84 to 68. The total number of decks on the tier list fell from 25 to 19. The adjusted average number of decks rose from 8.02 to 8.45, so the starting line moved up to 9. The adjusted standard deviation (STdev) rose to 13.62 from 11.46. This means that the aggregate Tier 3 begins at 9 and runs to 23, Tier 2 begins at 24 and runs to 38, and 39+ is Tier 1.

Deck Name	Total #	Total %
Tier 1
Izzet Aggregate	171	19.52
Rakdos Scam	79	9.02
Creativity Aggregate	77	8.79
Omnath Aggregate	60	6.85
Hammer Time	58	6.62
Rhino Aggregate	43	4.91
Tier 2
Yawgmoth	36	4.11
Burn	36	4.11
Amulet Titan	32	3.65
Mill	32	3.65
Izzet Prowess	27	3.08
Living End	25	2.85
Tier 3
UW Control Aggregate	20	2.28
MR Moon	14	1.60
MR Artifacts	14	1.60
MG Tron	14	1.60
Merfolk	12	1.37
Counter Cat	11	1.26
Humans	10	1.14

The first thing to mention is that thanks to the aggregation, Omnath moved over the line to be considered an outlier alongside the Izzet Aggregate and Rakdos Scam. It was therefore removed from the stat calculations as normal. The second thing to note is that this isn't actually as bad as I was expecting. I thought the data would be far more skewed.

Izzet Aggregate Ascendant

To the surprise of absolutely no one, the Izzet Aggregate was the top dog by a wide margin. Normal UR Murktide is already an outlier, and I added a whole bunch more decks to it. This result was inevitable. However, I thought it was going to be worse. As-is, Izzet rose to 19.52%, which is an absurd 10.50% above its next rival. But given that Murktide accounts for 6.85% of that gap, this isn't too terrible of an increase.

I'm not saying that holding almost 20% of the metagame is acceptable. In Modern's healthiest periods, no deck was ever more than 10% of the metagame, and there was minimal overlap between decks. This is closer to Standard numbers, with the worst I remember being Scars-Innistrad Standard where all the top decks started with Gitaxian Probe, [card]Delver of Secrets, and Geist of Saint Traft.

What I am saying is that I expected the overall aggregate to be much higher, up around 25%. I know how many different versions of the Izzet deck appear in my data and had it in my head that they took up a lot more space. It could be that thinking about all of this every month just lets it take free space in my brain. Thus, I was pleasantly surprised that it wasn't as bad as I expected. To be totally clear, though, it's still not good.

Omnath's Not Dead

Remember how after Yorion, Sky Nomad was banned, Omnath stopped being a boogeyman? Remember how many said that it was dead? That is clearly an exaggeration. What has actually happened is that midrange Omnath decks have heavily diversified. Where there were once only two versions that switched off in popularity, now there are enough variations to satisfy any pilot.

This aggregate category consisted of:

• 4-Color Elementals, which uses Risen Reef to get value off the evoking City of Solitude and Akroma, Angel of Fury.
• Tribal Elementals, which has all that plus more elemental tribal effects.
• 4-Color Control, which doesn't have Reef or any other tribal effects and runs more noncreature spells.
• 4-Color Blink, which exploits Ephemerate.

And a couple really niche builds that I don't have specific names for because they're singletons. Elementals is by far the most popular one, and even made Tier 2 in February. Blink is the next most popular and was Tier 3. Together, they moved the deck up to Tier 1. With all the other offshoots, it's the best performing non-outlier deck. That's quite strong for a supposedly dead archetype.

The Paper Aggregated Metagame

As the online data went, so too did paper. The total unique decks fell considerably from 108 decks to 90. The decks making the tier list fell from 23 to 20, which isn't as bad a fall as online. There was still only the one outlier, so the average barely changed from 7.37 to 7.47. The STdev did rise, from 11.80 to 13.85. Therefore Tier 3 begins at 8 and tuns to 22, Tier 2 begins at 23 and runs to 37, and Tier 1 is above 38.

Deck Name	Total #	Total %
Tier 1
Izzet Aggregate	146	17.87
Hammer Time	59	7.22
Creativity Aggregate	58	7.10
Rakdos Scam	56	6.85
Rhinos Aggregate	54	6.61
Amulet Titan	52	6.36
Omnath Aggregate	40	4.89
Tier 2
Burn	29	3.55
UW Control Aggregate	28	3.22
Merfolk	27	3.30
Yawgmoth	27	3.30
Tier 3
Living End	15	1.84
Mill	15	1.84
Affinity	13	1.59
Izzet Prowess	13	1.59
Counters Stoneblade	11	1.35
Domain Zoo	10	1.22
Mono-Green Tron	9	1.10
Jund Saga	9	1.10
Hardened Scales	8	0.98

The aggregated lists made it up to Tier 1, with only the UW Control Aggregate missing. It was just straight UW Control and two Esper Control lists in the first place, so that isn't unexpected. Izzet Aggregate's share of the metagame is lower than online, but the lead it has over Hammer Time is almost the same as online, coincidentally. Thus, everything I said a few paragraphs ago still holds true.

How Healthy is Modern?

The metagame's concentration around the Izzet core of Channeler, Ragavan, Bauble, Iteration, and Heat is quite high by Modern's traditional standards. There are many other strategies that hold large overall shares of the metagame despite being spread between multiple decks, many of which are quite different in terms of actual play. I genuinely thought when I decided to investigate this that decks like Creativity and Omanth would take up larger fractions of the metagame than they actually did. My excuse is that it's hard to wrap your head around all the data; you have to actually do the work for it to make sense.

It should be noted that if I defined the decks and how I aggregated them differently, then different outcomes would have emerged. For example, if instead of Omnath and Creativity decks I put all the decks that played Wrenn along with A-Teferi, Time Raveler. Such a grouping would include a number of decks not currently in this list and leave some of the Creativity and Omnath decks unaggregated. This would have dramatically changed the picture.

While there are many ways to define and redefine concentration, I think that constantly doing so is missing the point. That Izzet core is dominating Modern to an extreme degree. Wizards has declared that they have no intention in doing anything for the time being, so players will either need to join in or adapt. Given history, I expect the former to be the more popular choice.

It Is What It Is

For better or worse, this not-so-secretly stale format is the Modern that is going to prevail for the time being. The next opportunity for disruption and a change to the status quo will be the release of March of the Machines on April 21. After that, I expect Wizards to reevaluate their position.