Red-Green Eldrazi(needs some reformatting, tags, decklists)

Synopsis

RG Eldrazi is the spiritual successor to Bant Eldrazi. Both are Green Eldrazi decks that use Eldrazi Temple and Noble Hierarch to cast Eldrazi ahead of schedule. Both have a high degree of consistency thanks to the extremely powerful Ancient Stirrings. Both play the requisite playsets of Matter Reshaper, Thought-Knot Seer, and Reality Smasher. At this point, they’re playing 20 identical nonland cards; why go Red for the remaining sixteen instead of White and Blue?

Much of the deck’s power comes from Eldrazi Obligator, which can deal enormous sums of damage in a single turn and completely ruin your opponent’s plans, and Bloodbraid Elf, which we’ve seen shine since its unbanning for its ability to provide card advantage while simultaneously pressuring the opponent. Even RG Eldrazi’s removal spell of choice, Lightning Bolt, can serve an aggressive role in dealing the last couple of points to an opponent.

Like all Eldrazi decks, you need to be willing to mulligan aggressively, as your Temple/Hierarch games are far, far more powerful than games without any mana acceleration. In your opening hand, you’re looking for an Eldrazi Temple or a Noble Hierarch. Depending on how many times you’ve mulliganed and the composition of the hand, Ancient Stirrings can also push a hand into the keepable range. Regardless of the rest of the hand, 2-3 Ancient Stirrings and a green source also merits a keep.

Core Cards

As was aforementioned, RG Eldrazi, as an Eldrazi deck, will play the full playset of Matter Reshaper, Thought-Knot Seer, and Reality Smasher. The strength of these cards is well-established; all will frequently provide 2-for-1’s, are powerful when coming down a turn early, and pressure the opponent while also taxing their answers.

Noble Hierarch is the best replacement since Eye of Ugin’s banning that we have for Eldrazi Temples 5-8. In conjunction with Temple, it can provide truly busted starts that include Turn 2 Thought-Knot Seer into Turn 3 Reality Smasher. However, Hierarch only provides one of the deck’s two colors; why not run Birds of Paradise instead? RG Eldrazi’s manabase is good enough that it doesn’t actively need fixing; what it does need is ramp. Noble Hierarch’s upside of having Exalted stapled on is far, far more relevant than Birds of Paradise being able to make Red mana. Hierarch allows you to attack under Ensnaring Bridge, gain a leg up in midrange mirrors, and, in multiples, makes for enormous attackers. With the rise of Hollow One decks, Noble Hierarch allows every Eldrazi in your deck to kill the namesake card in combat.

Support Cards

Eldrazi Obligator has two modes. Its first mode shows up most frequently against control decks or spell-based combo decks, where there won’t be a great target for the Threaten ability and your gameplan is to maximize the amount of damage you’re dealing as quickly as possible. It shines as a hasty 3-power two-drop (if you’re playing the deck correctly and found Eldrazi Temple). The second mode is great against creature decks, particularly decks that are trying to play similar games to yours. Stealing a Tarmogoyf, Delve threat, Hollow One, or even a Primeval Titan can result in game-ending amounts of damage, since you’re both adding an attacker and removing a blocker simultaneously.

Also, keep in mind a few tricks with Eldrazi Obligator. First, the trigger targets on casting, and you choose to pay or not on resolution. That means that you can kill a Phantasmal Image out of Humans simply by paying 3 mana to cast Obligator. Second, if your life total is 13 or higher, you can steal a Death’s Shadow and kill it once you take control. You can also use Obligator to gain access to activated abilities you want. For example, stealing a Pia and Kiran Nalaar to sacrifice your Mind Stone and deal 2 to any source (including itself). Third, Eldrazi Temple can only add 2 mana when you are either casting a colorless Eldrazi spell or activating an activated ability of a colorless Eldrazi. Eldrazi Obligator’s ability is a triggered ability that you pay for upon resolution, which means Eldrazi Temple cannot provide two mana to pay for the Threaten. Aside from that slight downside, Obligator is a card that has a lot of play to it, and also just beats down nicely.

Bloodbraid Elf is a hasty four-mana 3/2, which by itself is a little underwhelming. It’s certainly in line with our gameplan, but you don’t see us playing Gruul Scrapper in our deck. However, in combination with its Cascade trigger, Bloodbraid Elf is a powerhouse. The most lackluster hits in the deck are Mind Stone and Noble Hierarch, but even those don’t feel terrible. Ancient Stirrings, Lightning Bolt, and Matter Reshaper are the next tier of quality.  Stirrings will find you a threat, Reshaper is a threat, and Bolt will either kill a threat or deal a cool three damage. But the best-case scenario is Cascading into Eldrazi Obligator and having two mana up (be sure to leave up a colorless!) to pay its cast trigger. If you have nine mana to pull this off (not unreasonable with Hierarchs and Temples), you get to add six hasty power to the board and convert an opponent’s blocker into an attacker for you.

As is often the case with Eldrazi decks, there aren’t enough good Eldrazi to play, so the deck is forced into running Mind Stone for the added consistency and late-game cycling or Scavenging Ooze because it’s a reasonable two-drop that can grow to the size of an Eldrazi, and is generally pretty good. Nest Invader is another option, as it provides a body and also some one-shot ramp. Dismember is common as a 2-of as additional removal that can deal with threats that have more than three toughness, such as Angler, Tasigur, Goyf, and Hollow One. It can also be used as a combat trick to allow your Eldrazi to fight favorably with opposing creatures, specifically combining well with the trample of Reality Smasher.

Manabase

You’re playing Eldrazi, so 4x Eldrazi Temple is required.

The deck is secretly three colors: Red, Green, and Purple errr, Colorless. This means that its best lands are the trilands, Karplusan Forest and Grove of the Burnwillows. When given the choice between tapping one or the other, it is usually better to tap Karplusan Forest; you’re an aggro deck, so giving your opponent life isn’t always the best decision. However, there are plenty of matchups where you need to place a higher value on your life total, and will tap Grove of the Burnwillows instead. Also remember that you can use Grove of the Burnwillows to kill Death’s Shadow!

Cavern of Souls is usually run as a 3-of. As usual, the card is fantastic, as this is a tribal deck. Not only is RG Eldrazi a tribal deck, but it is a tribal deck that is actively happy that Cavern can tap for Colorless. Just remember that if you tap Cavern for Colorless, your spell can be countered. Also remember that opponents who don’t play as much Modern will often miss this. Another tip with Cavern: back in the day, if you didn’t specify the color of mana you were making with Cavern, it was assumed you were making colorless, and your spell would be countered. Today, it is assumed that you are making uncounterable colored mana with Cavern unless your spell requires colorless and Cavern is the only source you’ve tapped that provides colorless. So if you don’t specify a color and an opponent tries to “get you” with a counterspell, just call over a judge.

The final utility land the deck runs is a single copy of Kessig Wolf Run. Like Obligator, you can kill Phantasmal Image with it, but it is more typically used to produce a combat step that your opponent cannot survive regardless of blocks. A quick burst of power and trample is a nice way to kill. Don’t forget to attack with Noble Hierarch as well, as Kessig Wolf Run can turn it into a lethal attacker.

To fix the rest of your mana, the deck typically runs 2x Wooded Foothills, 1x Stomping Ground, a couple of Forests, and 1x Mountain.

Matchups 

RG Eldrazi is a honestly a pretty fair deck. Like many decks in Modern, it has access to busted starts, but as the games go longer, Eldrazi Temple will become less and less relevant. Like most Eldrazi decks, RG Eldrazi tends to be favored against other fair midrange decks, such as Jund. You’re also favored against Control, with Cavern of Souls and your aggressive slant making it very difficult for them to stabilize. Grixis Shadow also feels good, as your top-decks are live, Obligator is an MVP, and so many of your threats are stapled to card advantage.

Your closer matchups are Burn, Affinity, Tron, and Storm. These are all decks that are trying to kill you quickly, which is the same thing you are trying to do to them. The die roll is obviously important in Modern generally, but particularly so here. Against Burn, Tron, and Storm, Thought-Knot Seer is one of your strongest card, as it allows you to interfere with their game plan and slow them down while still keeping on the pressure.

Unfortunately, RG Eldrazi’s Humans matchup is not so hot. Reflector Mage is a beating against this deck, and being able to Reflect a Smasher at instant speed and then name it with Meddling Mage makes it very hard to attack through. Like Merfolk (also a tough matchup), Humans can go both wide and tall very quickly, rendering your 5/5’s useless. Obligator tends to be your best shot at beating them, as you are forced into racing, and Obligator is really the only way you win a race. Bogles is also a terrible, terrible matchup for the deck. The moment they cast a Daybreak Coronet, the race is over.

Sideboarding

In your sideboard, you definitely need hate for the go-wide decks. All is Dust is certainly an option, though it tends to be a tad slow. The real competition in the slot is between Ratchet Bomb and Engineered Explosives. Explosives tends to be the faster boardwipe, but is a dud off Bloodbraid Elf, whereas Ratchet Bomb is a great hit off the Cascading Berserker. A consensus has not yet been reached, so do some testing and pick whichever you like better.

More removal in the board is also good: Ancient Grudge and Natural State are all-stars against artifact-based decks, and Natural State gives you a small, fighting chance against Bogles.

Relic of Progenitus is the best graveyard hate the deck has access to, since it’s not running White or Black.

A particularly spicy inclusion in a couple of sideboard has been Ulvenwald Tracker, a cheap creature that lets your creatures fight your opponent’s whenever you like. If you really want to put the midrange mirrors into “strongly favored” territory, or are just looking for additional, more flexible removal, Tracker is a great choice.

Other inclusions that you can consider based on your metagame are Kitchen Finks(Aggro decks and Midrange Decks), Kozilek’s Return(Aggro decks), Chalice of the Void(Death Shadow, Burn, Bogles), and Warping Wail(Scapeshift).

Conclusion

The Green-based Eldrazi decks are the “fairest” builds of Eldrazi (as compared to Eldrazi Tron or Colorless Eldrazi). While they tend to be more consistent, they are also less explosive. RG Eldrazi moves closer toward explosivity thanks to its aggressively-slanted Red cards, but if the metagame is dominated by extremely fast, linear, strategies, you should probably shelve the deck. On the other hand, if the metagame is a bit slower and grindier, RG Eldrazi is a fantastic pick to beat up on opponents with.