Oath of the Gatewatch significantly changed the face of Modern upon release. Even after the deck that the set spawned was hit by the ban-hammer, the Eldrazi have found a way to claw back to the top of the format. If you checked out the most recent Modern Metagame Breakdown then you no doubt noticed that Bant Eldrazi has risen once again to being the most played deck in the format. Clearly the current percentages don't match the deck's former dominance, though it is a deck that you can expect to play against frequently in Modern. As such, I would like to offer an in-depth breakdown of the deck, discussing both how it functions and its core weaknesses.
There aren't a ton of deviations in how to build Bant Eldrazi. Some players have advocated for Tarmogoyf at various times, though mostly the deck is just large Eldrazi, a handful of removal spells, powerful lands, and great sideboard spells. It's safe to assume that most lists will look very similar to Brian Braun-Duin's list from his World Championship win:
I wouldn't fault somebody tapping four mana to cast Thought-Knot Seer in Modern, though the backbone of the Eldrazi deck is Eldrazi Temple. Eldrazi Temple lets you cheat on mana, which is a consistent reason cited for banning cards in Modern, including the very similar Eye of Ugin. Many of the spells in the Eldrazi deck are overcosted for Modern by one-half to a whole mana—a land that taps for two suddenly makes these spells reasonable, or for some of the cards well above the curve.
Something that is important to understand when you look at the current Eldrazi decks, is that the deck responsible for getting Eye of Ugin banned mulliganed very aggressively and won a lot of games simply by virtue of a single Eldrazi Temple. The broken Eye of Ugin and Eldrazi Mimic draws got Eye banned, though the Eldrazi Temple and Eldrazi Displacer draws on five cards were often more than enough to win games. As such, many of the starts of the current configuration mirror exactly some percentage of the games that once completely broke Modern. The deck's ceiling has been lowered, though there are going to be times when you aren't sure if you're watching a post-ban or pre-ban game with the archetype.
What the deck lost in raw explosive power it has made up for in consistency with the adoption of Ancient Stirrings. Ancient Stirrings is undeniably the most powerful cantrip still legal in Modern, adding a ton of consistency to Tron, Lantern Control, Amulet Bloom, and now Bant Eldrazi. Stirrings smooths out draws and finds the missing piece for the fast openers, whether that's the appropriate threat for the situation, or an Eldrazi Temple to push the archetype to the limits of the format's power level. This improved consistency is precisely what makes the current iteration the force that it is.
The Case for Joinin' Em
The power of Ancient Stirrings is just one premise for the argument that Bant Eldrazi is more than just another linear Modern deck. The primary difference is that Bant Eldrazi is generally rewarded for sticking to its theme with cards that are individually powerful. Other linear decks, such as Affinity, Burn, and Infect, play a specific subset of narrow cards to maximize their game plan and consequently find themselves weak to hate cards. Bant Eldrazi, alternatively, is granted far more upside than downside by sticking to its theme. It gets a phenomenal card-selection spell in Ancient Stirrings, a land that taps for two mana in Eldrazi Temple, and the absurd upside of Cavern of Souls. Counters aren't the most popular spells in Modern, though I think it's worth mentioning given that the "hate" card we were given in Kaladesh is Ceremonious Rejection. Realistically, there's basically nothing you can add to your sideboard to give you a significant edge against Bant Eldrazi if you're struggling game one.
Given the abstract power level of Bant Eldrazi's spells, and its general resilience to individual answer cards, it generally crushes decks that are trying to force interaction. Thought-Knot Seer is big enough to demand specific removal spells in addition to providing disruption, while Reality Smasher is even larger and offers its own form of resilience. Drowner of Hope is larger still, with an extremely relevant ability in combat, and being a Flagbearer is just one of many talents of the consistently amazing Eldrazi Displacer. The composition of the deck and its general resilience allows it to effectively play the control in most matches, forcing the opponent to kill the Eldrazi player before the deck buries them with its huge spells.
Against the other linear proactive decks, Bant Eldrazi also fares quite well. The deck just needs less to go right for its individual spells to be great, and the deck both has very potent sideboard options and a healthy bout of disruption in its maindeck. Like other linear Modern decks, Bant Eldrazi will have to mulligan some percentage of its "lands and spells" hands. However, a high percentage of five- or six-card hands containing Noble Hierarch and/or Eldrazi Temple will be actively great, and Ancient Stirrings is arguably the best spell in Modern to have in your deck on a mulligan.
With all of these strengths, it is not surprising that Bant Eldrazi is currently the most popular deck in Modern, and I would not be surprised to see its metagame share grow. I would say it is definitely a great choice for the Star City Games Milwaukee Open this weekend, and I'd be rather surprised not to see at least one copy in the Top 8. If you're looking to pick the deck up, the skills you'll need to hone more than anything are assessing mulligans and managing Eldrazi Displacer, as those will be your two biggest avenues to throw away games. A couple rules of thumb are to mulligan any seven-card hand that doesn't have a mana creature or an Eldrazi Temple, and with regard to Eldrazi Displacer it will very frequently be better to leave up activation mana than to cast spells.
Combating Bant Eldrazi
The tone of the article to this point feels like I'm establishing a case for Bant Eldrazi being the best deck and/or worthy of a ban, though that's not exactly where I land. I would be totally on board with banning Ancient Stirrings and/or Eldrazi Temple, though we are far enough from the level of dominance that necessitates this that I don't see much reason to have that conversation. Instead, we should focus on the weaknesses that the deck does have.
For those not deeply entrenched in Modern, BBD's sideboard Worship may seem a bit odd, and it is included specifically as a trump for the mirror. Bant Eldrazi has a lot of difficulty with non-creature permanents that lock up combat, and a Worship can just stop your Bant Eldrazi opponent cold. Similarly, Ensnaring Bridge out of Lantern Control, with Pithing Needle backup naming Engineered Explosives, can make quick work of the deck. In fact, Lantern Control was one of few playable decks during the Eldrazi deck's original dominance. A board filled with Ghostly Prisons can similarly give the deck fits.
If you're looking for a single-card strategy to beat the deck though, then I hope you're into Blood Moon. Blood Moon makes it very difficult to generate colorless mana, and it's much more difficult to kill with an Engineered Explosives than Ensnaring Bridge. Notably, Eldrazi Skyspawner and Drowner of Hope will give the Bant Eldrazi player outs to your Blood Moon if you take your time killing them, though if you combine it with a quick clock you should have a solidly positive matchup.
Another way to be favored against Bant Eldrazi is with a fast clock that goes wide. Affinity and Elves are the primary examples of decks that can quickly make too many relevant bodies against Bant. The set of sideboard Stony Silence out of BBD's board can hose some Affinity draws, though Bant Eldrazi is basically dead to rites against Elves on the deck registration sheet. The Eldrazi deck simply does not have the tools to clean up boards that quickly go wide with a massive damage output. Once Elves starts snowballing, Eldrazi realistically can't catch up.
By most accounts, Merfolk is a pretty poor matchup for Bant Eldrazi too, given that Silvergill Adept enables a go-wide plan in addition to the small prison elements of Spreading Seas. There is definitely a ton of pressure on the Bant Eldrazi deck to draw its removal spells against Merfolk. That said, Merfolk is far from my first choice of tools to combat Eldrazi, given that it doesn't snowball or pressure the Eldrazi deck the way that Elves and Affinity do, and generally relies on more things going right. I am positive that Merfolk players will disagree with me on this, and I acknowledge that is likely not a universally accepted position.
I don't know if prison decks or non-creature combo decks are a smaller share of the Modern metagame, though both offer strategies that Eldrazi has difficulty interacting with. Thought-Knot Seer is a hell of a card, but they basically can't win without it against a good draw out of Ad Nauseam or Storm, and even with it they can still lose. Chalice of the Void out of the sideboard is definitely relevant for the Eldrazi deck in these matchups, but the combo decks can still beat it. Of course, some Stubborn Denials and/or Negates out of the Bant Eldrazi deck can make these matchups pretty positive for them post-board. If you weren't a combo player before, I don't think now is necessarily a great time to become one.
A Great Choice
Bant Eldrazi makes a strong case for being the best deck in Modern, and I think it's very telling that every type of strategy that could be used to hate it out is much more easily hated out itself. Many Modern decks can be defeated by individual cards, whereas Bant Eldrazi demands a commitment to specific strategies to be especially favored. If you're looking for a Modern deck to pick up, then Bant Eldrazi would be my recommendation. The archetype's current popularity is no fluke, and there's some very solid theory to explain how it carved out its favorable metagame position.
Thanks for reading.
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