In the vast card pool of Modern, there are quite a few hidden gems that are either underplayed or could see play in other strategies. Decks like Death's Shadow and KCI existed for a long time before being discovered. This leads me to believe there are plenty of other undiscovered viable decks lurking in the depths of Modern. Whenever I come across a card that sparks my interest, I take note of it. Sometimes I'll build some exploratory lists around it. In rare cases, I'll continue digging if I think there is something truly great in the idea. Over the years, these cards have formed a disorganized list in my brain of cards that could potentially take over Modern either in established decks or entirely new strategies.

In an attempt to make the list a little more organized, I want to document a few of those cards on that list. It is important to note that the decklists in this article are rough starting points and are far from polished.

Bomat Courier

Bomat Courier is an incredibly powerful card and has certainly demonstrated that in Standard. It presents pressure in the form of inevitable card advantage that must be dealt with, all at the low cost of one mana. Despite its efficiency, the deckbuilding constraints Bomat Courier puts on a deck are fairly significant. To cash in on the card advantage machine, you need to have few, preferably zero cards in hand. The type of deck that wants this card will be emptying its hand quickly to prepare to reload. Not many decks can or are actively looking to do that, but the ones that do will be happy to have it.

One deck I would look to for Bomat Courier is Burn. All Burn is trying to do is empty its hand of burn spells to put the opponent’s life from 20 to 0. That can be difficult to do sometimes when resources are tight. If the deck draws a few too many lands, it will often be six to nine life points short. Bomat Courier not only acts as a burn spell by chipping in for 2-3 damage, but it brings along with it the burn spells under it. Bomat Courier is at its best in a slimmed down version of Burn playing Bump in the Night. My biggest issue with traditional RW Burn are the hands that die with two-mana spells rotting away in hand. The lowering of the curve will both help kill the opponent quicker and make Bomat Courier better.

The other deck I propose we add Bomat Courier to is Death’s Shadow. The deck is all about playing the most efficient spells possible, and what better than a one-mana draw-four? That characterization is a bit of an exaggeration, but the card is still a perfect fit. The deck plays removal spells to let Courier get hits in, and it plays hand disruption to quickly trade off resources. If both sides are constantly trading one-for-one, but one side has a Bomat Courier, it is clear which side will win.

Erayo, Soratami Ascendent

Erayo, Soratami Ascendent may fit more under the category of pet card rather than secretly powerful card in Modern. Part of me just really wants this card to work, but I should still try to honestly evaluate this card. When looking at the power of a card, It is important to weigh the setup cost against the payoffs. If the payoff does not overcome the amount of setup required, then the card is not worth playing. If it feels like you are having to do too much to make a card work, than you almost certainly are.

Now, the payoff for Erayo is pretty strong. Countering the first spell an opponent plays each turn will slow them down a lot, and in some cases, just lock them out. It won’t win the game on its own, but it won’t need too much help. What is the setup? Cast four spells. That is a lot of spells. That is more than half the number of cards in a starting hand. I think most people would stop at that and move on to something else. They are probably even correct in doing so, but it is possible this card is playable now with Mox Amber and Sai, Master Thopterist.

Casting four spells in one turn is no small order. Doing it consistently is even more difficult. Accomplishing it, and then still having enough resources left over to win the game, is seemingly impossible. Needless to say, Erayo, Soratami Ascendent has the biggest deckbuilding constraints of any card on this list. To cast four spells in a turn, the deck needs to be filled with tons of free spells. That almost certainly locks us in to playing artifacts. If we have Erayo in hand, we certainly want to be able to consistently flip it on turn two. That means we need mana ramp. This cross section pushes us towards Mox Opal and Mox Amber. Mishra's Bauble gives us a free spell that also replaces itself. Round out the zero-cost artifacts with Engineered Explosives for some disruption and we have a nice core. Without Mox Amber, this core would not be consistent enough to work.

The enchantment side of Erayo is pretty good, but not good enough to end the game on its own. We need threats to end the game that work well in a deck filled with zero-mana artifact spells. The two cards that work perfectly in that environment are Monastery Mentor and Sai, Master Thopterist. Again we run into more redundancy. We have up to eight copies of a card that will end the game shortly backed up by a pile of zero-mana artifacts.

A couple notes about this list as a starting point. Repeal is the key. Either Mox with a Repeal is enough to flip an Erayo the same turn you play it. It also combos well with Monastery Mentor and Sai, Master Thopterist.

The one Chalice of the Void is pretty awkward. You don’t really want to cast it on zero unless there is no other way to flip Erayo, as it locks out a lot of the other spells in the deck. I could see cutting that one immediately. I like having a Rule of Law type effect in Ethersworn Canonist. It assembles the true lock with Erayo’s Essence, and is even an artifact for Mox Opal. Overall, this is a pretty good starting point—despite my bias, I’m confident it has a lot of potential.

Utopia Sprawl

Utopia Sprawl is a unique ramp spell in Modern. It is a one-mana ramp spell that is not a creature. If you want that type of effect in Modern, typically you would have to play Noble Hierarch or Birds of Paradise. Unlike those staple mana dorks, Utopia Sprawl isn't vulnerable to removal spells, which makes it more reliable. We've seen a little bit of Utopia Sprawl in Modern in decks like Ponza or Green Devotion, but I think it could easily spawn other archetypes.

Utopia Sprawl puts a lot of constraints on the land choices in a deck. The majority of the basics and dual lands need to be Forests. This forces any deck relying on Utopia Sprawl to be base green. This constraint is a big reason why we've only seen it in mostly green decks. Getting to choose the extra color the land taps for is a form of fixing, and we should be able to get a little greedier with our color choices. Thanks to shocklands, Modern manabases can support three-color decks while still having enough Forests for the land enchantment to function.

The place I'd start brewing with Utopia Sprawl is a bigger midrange deck. Midrange decks in Modern need to play a lot of one- and two-mana plays, so that they can keep up with the other decks in Modern. With Utopia Sprawl, we could play some three-, four-, or five-mana haymakers to get us back in the game. We could play three-mana wraths like Sweltering Suns or maybe a Liliana. With four mana we could play a Jace, the Mind Sculptor on turn three. For five mana, we could look at cards like Thragtusk or Teferi, Hero of Dominaria. There are a wide range of options available in all four of the possible supporting colors. Figuring out exactly what the deck wants would require a lot more testing than theorizing.

There are a few things working against Utopia Sprawl in Modern. Most green decks are interested in playing creatures. Part of green's color pie is that its power is largely focused in creatures. In decks built around creatures, there is not much incentive to play Utopia Sprawl over the one-mana creature accelerators. Most of the good noncreature midrange payoffs are in other colors. This pushes the deck away from base green. Utopia Sprawl is also lacking an effective second copy of it. Noble Hierarch has Birds of Paradise. Any deck built around having Utopia Sprawl in play will run into consistency issues. But if we ever do get copies five through eight, Utopia Sprawl will be the very next card I start brewing around.

Mausoleum Secrets

Mausoleum Secrets is a bit of a bold prediction. This card could very easily never see play in Modern. It is a two-mana tutor though, and that is very exciting. Modern does not have many tutors on the cheap. Traverse the Ulvenwald requires too much setup to reliably be used in a combo deck. Time of Need is a bit too narrow to be effective. Summoner's Pact has been the most impactful in Modern, seeing play in Amulet Titan and Valakut, the Molten Pinnacle strategies. Mausoleum Secrets might fall into one of these categories, but I can’t really be sure without playing with it.

The biggest thing that Mausoleum Secrets has going for it is the recent printing of Stitcher's Supplier. Combine it with Hedron Crab, and that is a quick self-mill engine based around creatures. I could possibly even see a couple Minister of Inquiries for redundancy. Previously, graveyard-based decks would rely on spells like Faithless Looting and Cathartic Reunion, but now the enablers can also count towards the creature count needed for Mausoleum Secrets.

The first shell I thought of for this card was Goryo's Vengeance. The main weakness of Goryo’s is that the deck has too high of a fail rate. On top of that, the Through the Breach plan is a bit too disjointed from the Goryo's Vengeance plan. One part of the deck is trying to dump Griselbrand in the graveyard and reanimate it with Goryo’s. The other half needs fast mana and a Through the Breach.

There is an awkward tension between the two packages. Faithless looting is card disadvantage, which is great for an all-in, graveyard-based combo deck, but makes it difficult to hit a bunch of land drops or rituals for a five-mana spell. Goryo's Vengeance wants the payoff to be in the graveyard, while Through the Breach wants the payoff in hand.

Not only is the strategy overall awkward, it is fragile too. One or two discard spells or any graveyard hate is often enough. All of that aside, Goryo's Vengeance on Griselbrand is a powerful combination that leads to a number of turn-two kills.

What excites me most about adding Mausoleum Secrets to the Goryo's Vengeance/Griselbrand shell is that we can cut the Through the Breach package. With Mausoleum Secrets to provide redundancy as a tutor for Goryo's Vengeance, we can go all in on that plan.

I’ve played around with a few different shells of the deck. My first build used Street Wraith and Insolent Neonate as ways to enable Mausoleum Secrets. I found that build to be just too inconsistent. Neonate is great at enabling Secrets, but rather poor at digging for pieces of a combo. My favorite version I tried is a turbo self-mill version with Stitcher's Supplier and Shriekhorn. I tried Hedron Crab, but found it a little too hard on the mana. Despite that, I think a Hedron Crab version still deserves some more exploring.

My main goal with this deck is to keep intact the powerful turn-two kill potential, but add consistency through self-milling and Mausoleum Secrets. I really like Stitcher's Supplier as a tutorable self-mill target. It won’t come up often, but it is nice to have. Switching over to Conflagrate instead of Borborygmos Enraged as the win condition makes only one to two activations of Griselbrand lethal. This might make the Nourishing Shoal package obsolete as you do not need to draw the deck to win.

The main weak point for any shell I've looked at is finding a copy of Griselbrand. The entire deck is based around getting him into play, and it really doesn’t do anything without him. I’m hoping that all of the self mill will be enough to find one, but there are still only four copies in the deck. It is possible there exists a green version with some number of Time of Need to help mitigate this issue.

Wrapping Up

I hope my dive into these cards gets you excited to do some brewing, or to look deeper into some cards you think are overlooked. I plan on revisiting this list from time to time to construct a potentially referenceable list. I would be interested in hearing what cards you think deserve a spot in the comments.