Modern Tron is known as a Karn deck. Assembling 7 mana as early as turn 3 makes it a no brainer that you should be casting the most powerful 7-drop colorless spell in Magic, right?

Well, not so fast, says Autumn Burchett. After her team’s Top 64 finish at Grand Prix Stockholm, Autumn tweeted the following:

In an effort to improve their deck against U/W, Autumn cut three of the Karns to increase the number of World Breakers in her deck before proclaiming her belief that this is the correct way to build Tron. So, is it time to put away some Karns?

I’m definitely at some risk of being on the wrong side of history here if everybody is crushing Modern GPs in a couple months with one or fewer copies of Karn Liberated in their deck, but I’m willing to go on the record and say that this is a very large error. I still believe Karn Liberated is one of the cards that contributes most to Tron’s success.

Karn is your best turn-3 play when you’ve established Tron in a number of matchups. Yes, there are aggressive decks that can force you to minus Karn and then lose it in combat, but that’s not the end of the world. It sounds bad to spend 7 mana on a removal spell and 3 life, but if it’s your turn-3 play, it’s a pretty curve. Even the aggressive decks don’t always get on the board that quickly. In those cases, sometimes Karn can tick up and begin to take over, and sometimes Karn’s minus will remove the only threat.

The reason for cutting Karn, as stated in Autumn’s tweet, was to improve the U/W matchup. Depending on who you ask, you’ll hear widely different responses on how it plays out. Many U/W players will say that they believe it’s favored, but I think the majority of the player base does not believe that to be the case. The spells U/W used to play, like Spreading Seas and Remand, combined with a playset of Field of Ruins, can make the matchup highly favorable for U/W, but we don’t live in that world anymore. With decks like Humans and Hollow One threatening quick kills, nobody has time to “spread ‘em” or to Remand anything. I believe Tron is favored versus current builds of U/W.

Being favored, or even if I’m wrong and U/W is  ahead, doesn’t mean the matchup can’t be improved. That said, Karn Liberated is absolutely not one of the weaker cards in the matchup! The countermagic suite a U/W deck typically plays has little in the way of cheap counters, and there’s no guarantee that a few Logic Knots will even be on for turn 2. If Cryptic Command isn’t at the ready, the odds of an early Karn resolving are high. It’s possible World Breaker is better than Karn against U/W as a recursive threat, making it stronger against countermagic, but that’s it. Keep in mind that the rest of their removal spells are often things like Path to Exile, Detention Sphere, and Terminus.

World Breaker is also incredibly challenging to cast on turn 3. The number of ways to establish turn-3 Tron so that you can cast a Karn Liberated are plentiful. If you lead on Tron land and Map, any other Tron land gets you there. If you have 1 of the 8 Chromatic artifacts to go with a Tron land, you can pair them with something like Sylvan Scrying or Ancient Stirrings to establish Tron if you had any other piece, and you will have 2-3 looks (depending if you’re on the play or draw and including the sacrifice of your Star/Sphere) to help you get there.

The number of ways to have a turn-3 World Breaker? Well, you need to draw natural Tron and also have a Chromatic Sphere/Star, or have two Tron pieces, two Chromatic Spheres/Stars, and an Ancient Stirrings that finds you the third piece. You can’t even use an Expedition Map to ever cast a turn-3 World Breaker! Now, turn-3 World Breaker isn’t always necessary, but you’re limiting the number of good draws you’re capable of. You’re also sacrificing amazing amounts of equity in mirror matches and against combo decks by not having that early Karn potential! Modern is not a format where you can afford to start doing meaningful things on turn 4 too often, so losing out on those turn 3s is huge.

While World Breaker is better than Karn against U/W, it’s not by a massive margin. Once you factor in that you can’t reliably cast World Breaker on turn 3 (nowhere near as often as Karn), you’re looking at a turn-4 play, assuming you’re uninterrupted. If that’s the case, this deck would have had the potential to instead cast a turn-4 Ulamog over that World Breaker. If you’re looking to play a slower game, the addition of Emrakul goes a long way toward beating U/W specifically, but it’s unfortunately poor in most other matchups.

Karn is also really good against U/W. Sure, it needs to resolve, but they don’t pressure it very well once it does. This list still runs all four Oblivion Stones, three Wurmcoil Engines, and goes up to four Walking Ballistas. None of these cards are particularly effective against U/W, although all have uses in their own right. The other card that’s truly incredible against control decks is Ulamog, the Ceaseless Hunger, and there are only two copies here. I believe that the Tron versus U/W matchup is favorable, and adding World Breakers can improve that, but I don’t know if your win percentage is actually increased by cutting Karns versus U/W, and I feel confident you’re going to lose more matches overall versus any Modern field, even one littered with U/W decks.

A quick aside on playing Field of Ruin in Tron—I believe this is also an error. As someone who went up to two copies of Ghost Quarter in their Tron deck for Grand Prix Detroit, I understand the need to interact with lands, but this card is a trap. The decks I most want the extra Ghost Quarter effects against are the mirror and Inkmoth Nexus. In the mirror, you want to be able to blow up the early Tron, and Field of Ruin often doesn’t even give you this option. Leaving 2 mana and Field up against aggressive Inkmoth decks is near impossible. Now, I’m well aware that Tron never wants to lose its lands and Ghost Quarter can really suck, but I think you only want to use it in spots where you realistically don’t have much of a choice. Tron has plenty of great ways to blow up lands in the mid-game, so Field of Ruin for Colonnade or Azcanta isn’t necessary in this deck.

Feel free to flame me mercilessly if I end up being wrong down the road, but I would absolutely not cut Karn Liberated from my Tron deck!

Tron

Autumn Burchett, Top 64 at GP Stockholm