Hey everyone! I normally pop off the prerelease guide and don’t write much more on sealed because I prefer to focus on draft. Then out of nowhere we get hit with this new Arena Direct thing where we can win a box of real life MH3. That leaves me to go back to this and update it with some of the info I’ve gleaned from my sealed adventures so far.
Modern Horizons 3 is a high-powered set with a lot of crazy things going on that require a bit more understanding than usual. I’m here to help you prepare for your Arena Direct experience by discussing the process for building your sealed deck in this format as well as providing you with a bunch of tips and tricks to give you a leg up on the competition.

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Building Your Sealed Deck
The first step of building your sealed is always to sort out your power cards. This will include your busted rares, mythic uncommons, good removal, and even your build arounds. In case you aren’t in the know, this includes Writhing Chrysalis. This lets you know what your pathway to victory is. It also lets you keep an eye out to see if your pool can support the build arounds.
The next step is to pull out all of your mana fixing. This includes the sacrifice lands (landscapes and OG ones), any dual lands, and mana dorks such as Nightshade Dryad. In this set, it also includes Sage of the Unknowable and other cards that can produce colorless mana.
Since there are a lot of cards that require specifically colorless (and can’t be paid for generically by colored mana), you have to sort of look at it like a sixth color. You should be able to support it, but make sure you’re not putting too much pressure on your mana base by doing so.
Now go through the rest of your cards and separate each color into cards you want to play, cards you’d situationally play, and cards you really don’t want to play. This lets you evaluate how deep each color really is and prevents you from thinking a color is good when it is mostly filler. One of the important things here is that there are different plans within each color, some of which don’t play well together, so you need to look at that to.
Next you want to start looking at how each color combination would look. This lets you see how the curves would play out, how the removal suites look, and if the decks have any serious weaknesses. You can then see if you can patch up those weaknesses by splashing.
At this point you need to be honest with yourself about whether or not your deck can get there on power level compared to other decks. If not, then you want to see if you can possibly build a low to the ground aggro deck to go under the greedier decks. You should also keep this in your back pocket as an audible to side board into against decks with a significantly higher power level.
Now you just have to figure out your mana base and you’re on your way to win some packs.
Tips and Tricks
While much more difficult to pull off in sealed, you do want to make sure your cards are on the same plan. There are a ton of cards whose value heavily fluctuates if your deck isn’t focused enough. A lot of the energy cards are fine on their own, but get significantly better with a critical mass of producers. For example, Galvanic Discharge is great in any deck with red mana while Unstable Amulet is terrible if you don’t have any other energy producers.
The Eldrazi decks have felt amazing in draft, but make sure you actually have enough colorless mana to support some of them. I know I have mentioned this in both sections, but you really don’t want to accidently put cards that you can’t cast into your deck. Breaker of Creation is a great card when you can reliably play it on turn six, but you don’t want it at all in a deck that is going to have trouble producing double colorless.
Sealed tends to be slower since the decks are less focused, that means those really expensive game shifting cards are much more likely to actually hit play. This is especially true with all of those Eldrazi Spawn tokens running around. While this is still a very fast format (even in sealed) you usually can play your bangers.
That doesn’t mean you should just throw Emrakul, the World Anew into an average sealed deck. You need to have enough Eldrazi spawn creators and ramp to support that.
Counterspells are another thing that plays better in sealed. They also tend to perform better in a high-power format which means they are doubling down here. Invert Polarity can be a game changer and can be worth splashing the red part for.
Making a mana base is a little more complicated here because of the need for colorless mana and the presence of MDFCs.
My rules for making your mana base with MDFCs are that the ones you are hoping to cast are counted as spells while the ones that are just a nice bonus if you draw them late are counted as lands. When they are more in the middle of whether you want to cast them, I count three MDFCs as two land slots.
Don’t play an MDFC if there is very little chance that it can ever be cast. I’ve seen too many people splashing Pinnacle Monk without any realistic way to cast it.
While the mana fixing appears plentiful, you’re still usually better off with two colors and a splash than the straight three colors.
While it is instinctual to pop your sacrifice lands to thin your deck, make sure you don’t still need that colorless mana the common landscape can produce before you do it.
Wastescape Battlemage has been a massive overperformer so far. Just like the old IPA Battlemages, it often ends up as a three for one deal.
Nightshade Dryad is another card punching above it’s weight class. Deathtouch plays very well in this format and it can provide any color or that crucial colorless you might me missing.
A cool thing to remember about the Landscapes is that the cycling colors at the bottom are a visual reminder of what lands they can fetch.
Hope-Ender Coatl is appropriately named because it’s such a huge blow when you get got by it. Be wary of that and Aether Spike when considering if you’re playing into them.
Aether Revolt is one of my favorite cards in the set. Unfortunately, you’re going to have to get really lucky to both open that and enough energy to make it worth it.
Don’t play any of the medallions, they are constructed traps.
Both Writhing Chrysalis and Titans' Vanguard have been playing insanely well so they could be pretty big draws into Gruul Eldraz. [note: it took all of 5 minutes of early access to figure this out so I’m just leaving this in here as is.]
It might seem like a meme, but Colossal Dreadmask is a great way to get across the finish line with a grindy deck lacking other ways to go over the top.
Eldazi are colorless, but that doesn’t mean they are artifacts. I’ve seen plenty of people try to use artifact kill on them already.
Per usual, I’ll finish off with the best piece of advice I can give you. The best thing you can do in sealed is to get lucky on your opens. It’s not that you can’t win with a mid pool, but it sure does make the day feel better when you bust the nuts. It’s also a lot easier to get six wins before two losses when you have an insane pool.
Wrap Up
Thanks for reading! Hopefully this helps you stack up some boxes of Modern Horizons 3 in the Arena Direct. I’ll be back soon with some more content for you. Until then, stay classy people!
If you have any questions, let me know in the comments below.
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