For the last few months, I’ve been doing nothing but playing Modern. Oddly enough, I played a different deck at Pro Tour Bilbao, Grand Prix Toronto, the Magic Online Championship, and Grand Prix Phoenix.

Of all of the decks I played, the one I was most impressed with and felt had the most format-breaking possibility was the Krark-Clan Ironworks deck I played at Grand Prix Phoenix. After the unbannings and the field at the MOCS, it felt like there were not going to be a lot of Stony Silences or Rest in Peaces floating around, and a powerful artifact combo deck like KCI seemed like the perfect choice to catch people unaware.

KCI

Andrew “BK” Baeckstrom, Ben Weitz, Matt Nass, and I worked really hard on this deck, iterating until we got our list to a point that we were ultimately quite happy with. Ben, BK, and I all ended up going 11-4 while Matt unfortunately lost in the semifinals to some thrilling Dark Confidant flips. Our overall win rate excluding byes was a robust 72% and I think KCI should remain a real contender going forward.

Breaking Down the Engine

The core engine of the KCI deck involves using KCI to generate a ton of mana and cards by sacrificing artifacts that draw a card when they die in conjunction with Scrap Trawler to return more of them as you go. Ultimately, you have a few different deterministic loops that let you draw infinite cards, make infinite mana, or infinitely loop a Pyrite Spellbomb from your graveyard. I’ll outline them below so you can recognize them easily, but first let’s break down the individual card choices.

Krark-Clan Ironworks & Scrap Trawler

These are obviously the key engine pieces of the deck. Your win rate will be a lot higher if you manage to get both of them into play, and it’s almost impossible to win without finding a KCI at some point.

Eggs

These are your cantrip artifacts. You’ll spend the early game playing them to help find KCI and have some bonus mana in play. Generally, I don’t mind cashing them in early if I think there’s a good chance that it will make my pre-KCI turns better (like finding a Mind Stone).

Mana Rocks

These are your accelerants. Mox Opal obviously needs no introduction and is one of the most busted cards in Modern. Mind Stone is a more occasional role-player, but fits pretty well in this deck. You play Mind Stone instead of something that’s better at generating mana like Everflowing Chalice because of its ability to essentially cycle for 3 mana (and net a Sphere/Star/Terrarion if you have a Trawler out).

Tutors

These help you find KCI for the most part. Stirrings in particular is very good because you often end up with spare green mana while you’re going off and it can help dig for additional Trawlers or Wellsprings if you’re going to end up short on cards. Fair is a little slower, but can also help get you out of a jam by tutoring for Engineered Explosives if you’re being disrupted.

Removal

These are your answers to annoying permanents in game 1. You have a nice diversity so you’re capable of winning even if your opponent manages to get two Meddling Mages into play. Pyrite also just works pretty well when you’re going off by being a cantrip artifact if that’s what you happen to need.

Zero-Cost Artifacts

These are the one-of zero-cost artifacts. They can be used to generate additional mana while going off, or just used for their “fair” functions in the earlier turns. One cool trick with Bauble in particular is returning it with Scrap Trawler triggers off of Spheres/Stars in games where you’re having a hard time finding a KCI.

Emrakul

You also have an Emrakul, which we were actually really unsure of. When you play the deck on MTGO, you really need Emrakul because it makes things go so much faster, but in paper play, because you can demonstrate loops, I think it might be unnecessary. But we had been winning a lot with the deck on MTGO and were reluctant to make too many changes from what we’d been testing. You can also occasionally cast Emrakul from spots where you maybe weren’t able to completely go off by just generating a ton of mana. Watch out for those spots because it’s usually good enough to kill with.

The Deterministic Kill

In Play

In Graveyard

In the graveyard can also be KCI.

With this loop, you float a mana with the Mox Opal, sacrifice it to KCI, then sacrifice the Retriever to return the Opal with its trigger from Scrap Trawler, and the Scrap Trawler with the Myr Retriever. Replay Opal and Trawler, float another mana, then sacrifice the Opal. Next, Sacrifice the Scrap Trawler to return the Retriever and the Opal. Replay them both and you’re back where you started but with 5 additional mana. This loop can also include a Sphere/Star or Terrarion to draw infinite cards. Finish them off with an Emrakul, or loop the Pyrite Spellbomb in the same way for extra style points. During the combo, you’ll also draw an Engineered Explosives that you can loop (and Mox Opal for lots of colors) if you need to beat something like Ensnaring Bridge or Witchbane Orb.

The Fancy Kill

You can also assemble a deterministic kill out of the following seemingly meager parts in play:

The Chromatic Sphere can also be a Chromatic Star.

The way it works is as follows:

You declare that you want to activate the mana ability of your Star/Sphere.

To pay for the 1 colorless mana part of the Star’s ability, you announce that you want to sacrifice Myr Retriever, your Mox Opal, and the KCI itself. You’re allowed to activate as many mana abilities as you want to pay, and again because you’re in the middle of paying for a cost, the triggers created by both Retriever and Scrap Trawler cannot be placed on the stack.

Now that you’re done paying for both parts of the cost, the ability resolves immediately (because it’s a mana ability) and the triggers you’ve been accruing have to be placed on the stack. First let’s discuss the triggers from your Scrap Trawler: The one generated by Krark-Clan Ironworks should target Myr Retriever, the one generated by Myr Retriever should target Chromatic Star, the one generated by Chromatic Star should target your zero-cost artifact, and the one generated by the zero-cost artifact has no legal targets. Next, the trigger generated by Myr Retriever dying should target the KCI. Additionally, because your Star went to the graveyard, it generates a “draw a card” trigger that also needs to be placed on the stack.

So at the end of all this, you get all the cards you sacrificed back, in addition to 7 mana (one of which is the color you picked for the Star) and a card drawn from Star’s death trigger. Conveniently, it costs 7 mana to put all of the stuff you returned right back into play, leaving you with the same board position you started from and plus one card in hand, so you can iterate this loop to draw a card. From there, you should be able to set up the deterministic kill outlined above and winning is as easy as putting Emrakul into play or looping Spellbomb.

This loop does work with Terrarion (sort of) but you need two of them. In that case, you announce that you want to cast one of the Terrarions, and to pay for it you sacrifice everything listed above as well as the other Terrarion. This nets you a card and all of the cards returned to hand, then you play all of the non-Terrarion cards you returned, and you’re back where you started (but plus one card).

Sideboarding

As with all combo decks, a lighter touch while sideboarding is critical. You can’t afford to have too many cards that don’t work with your core engine or you’ll start drastically increasing your fail rate. Generally it’s safe to cut down on Mind Stone, Terrarion, Chromatic Star, and some of the zero-drops while sideboarding. Rather than provide a sideboarding guide, which is going to be very dependent on what your opponent is up to, I’ll talk about what each card in the sideboard is for.

This is good against anyone who is either leaning heavily on Negate-type effects (think Death’s Shadow) or attrition (Jund). You’ll eventually get a ton of mana into play and can just hardcast it. Remember that if you have a KCI in play you can sacrifice it in response to nasty things like Path to Exile

Your anti-counterspell package. We decided that Guttural is the better card, but because you can Stirrings for Defense Grid, we wanted a mix. Remember that Grid is a symmetrical effect, so if you’re playing against something like Storm, you won’t be able to use a Guttural Response to counter a Gifts Ungiven while they’re going off unless you leave 4 mana up.

The most important sideboard card because it answers most of the cards that just beat you. It kills all the white enchantments, Leyline of the Void and Eidolon of the Great Revel. Don’t forget that you can also Claim your own permanents (mostly Ichor Wellspring) if you need to dig a little deeper and think that you don’t need the Claim for later.

A versatile card, Brutality gives you more options to kill creatures like Meddling Mage or Gaddock Teeg, as well as a Duress effect against counterspell or combo decks.

Another card that can get around the white enchantments out of slower decks. You can also easily lock out Humans, Elves, Infect, or Affinity with a strong Grid draw.

You don’t care a ton about most graveyard decks, but Nihil Spellbomb works so well with the rest of your deck’s game plan that including it is a pretty low cost. You’ll want it against anyone trying to do graveyard shenanigans, and don’t forget that it can still draw you a card even when sacrificed to KCI.

Tips and Tricks

• Try to avoid playing a land before you go off if it’s easy to do so. If you start to fizzle, it’s often because you’ve drawn a bunch of lands, but Buried Ruin and Inventors’ Fair are good at getting you back on track by adding more gas to your hand.

• Speaking of Inventors’ Fair, it’s legal to use KCI mana to pay for its activated ability even if it would put you below three artifacts in play to do so. It doesn’t come up often, but you’ll be happy you knew when it does!

• You usually want to play your Ichor Wellsprings as soon as possible while going off because they could draw you into additional Scrap Trawlers, which really let you go nuts with the card drawing.

• Once you start going off, it’s way more likely that you need more cards than that you run out of mana, so try to make decisions to maximize cards.

• Be aware of Stony Silence and Rest in Peace if you’re up against a white deck. I’ll bring in at least a couple Nature’s Claims against anyone with white mana in their deck, but you also need to make sure that you are using your cantrip artifacts so you don’t end up in a situation where you can’t sacrifice them to dig because one of those annoying enchantments is in play.

• Remember that Chromatic Sphere only draws you a card if you use its mana ability, so you usually need to do that rather than sacrifice it to KCI

• To play around removal on Scrap Trawler, it’s usually best to get as much into play before you cast Trawler as you can. Then if your opponent goes to remove it, you can sacrifice a handful of artifacts and generate as many triggers as possible before it dies.

That’s all the news that’s fit to print about this old/new Modern archetype. I think the format might become more hostile for a little while, but you’ll be well served to remember that this option is available if people start to sleep on their white sideboard cards!