The Grinding Station and Underworld Breach combo deck is a personal favorite of mine. It helped me qualify for my first Player's Tour back in 2020 and has recently seen a resurgence in popularity thanks to the recent success of both @tiddypills and @brittney_mtg. The current builds that they've pioneered have moved away from an all-in combo to a multifaceted approach. Ragavan, Nimble Pilferer and Dragon's Rage Channeler provide an aggro plan, and Urza's Saga lets you dominate a long game.
These threats divert attention away from the deck's ability to still slam your A+B combo to win the game out of nowhere. Grinding Breach has a lot of positive parallels to Modern's old Splinter Twin combo and I highly recommend it for the Twin die-hards out there.
I had planned my article for this week well ahead of time, but I'm happy to report that I'm also practicing what I preach! This weekend I took Grinding Breach to a top 8 finish at a local $1k and it outperformed expectations, navigating seamless victories through plenty of disruption.
What Does It Do?
This combo features Underworld Breach, a card that lets you cast spells from your graveyard by paying their mana cost along with exiling three additional cards. Unlike similar versions of this effect like Yawgmoth's Will and Past in Flames, Breach is inexplicably less mana and puts the cast spells back into your graveyard. This lets you play the same spell over and over as long as you have enough fodder to exile.
That's where Grinding Station comes in. You can tap it to sacrifice an artifact and mill a player three cards. And very importantly, when you have an artifact enter the battlefield under your control, you untap Station. This combined with any zero-mana artifact like Mox Amber and Mishra's Bauble allows you to mill your entire library.
Doing this loop with Amber nets a blue or red mana with each iteration depending on whether you have Emry, Lurker of the Loch, Ragavan, Nimble Pilferer, or The Reality Chip in play. After sufficiently milling your deck, you can win with Thassa's Oracle or by casting Lightning Bolt multiple times.
Notably, if you're not constrained on mana, you can loop two copies of Emry with the legend rule to mill four cards in your sequence instead of three, adding additional cards to the graveyard to use as fodder. This may come in handy for the Lightning Bolt plan. Similarly, Dragon's Rage Channeler can perform a similar function when casting your Mox or Bauble thanks to its surveil trigger.
Provided that you have at least one additional mana available when initiating the combo, it doesn't matter if you have a legendary creature in play at the start of the loop to create a deterministic kill. You can simply cast it from the graveyard and recoup the mana with Amber. With two open mana, you don't even need the legendary creature.
What I Like
Grinding Breach gets to fight on three separate axes that your opponent needs to answer and respect, but answers to one don't often cleanly deal with the others.
About a third of your deck is identical to Izzet Murktide, one of the top-performing decks in Modern. You have the same aggressive threats in Ragavan and Channeler, the same removal suite in Lightning Bolt and Unholy Heat and the same card selection and advantage tools in Mishra's Bauble and Expressive Iteration.
Unlike Murktide, you have access to Urza's Saga and Emry, Lurker of the Loch. These additional threats stretch your opponent's removal while providing even more card advantage by creating multiple must-answer creatures or drawing additional cards. Saga tokens can also just become outright massive. It's not uncommon for these to be the largest bodies on the board, and saddling them with Shadowspear wins the race against any fair deck.
On top of this, your opponent is forced to respect your two-card, four-mana combo at all times. That means they need to prioritize finding and keeping multiple forms of graveyard disruption or hold up countermagic. That's a big ask when they're facing a fast creature-based clock. Even without the full combo, playing a fair Underworld Breach to rebuy multiple removal spells or multiple redraws with Mishra's Bauble can be massive swings.
While less tangible and harder to quantify, Grinding Breach is not an intuitive deck to interact with if you're unfamiliar with it. Your opponents will be more likely to counter the wrong cards, fire off their graveyard hate at the wrong time, name the wrong card with Pithing Needle, etc. Being able to capitalize on your opponent's mistakes is an absolute benefit to this deck that should be considered.
What I Don't Like
Since the deck does just about everything, it gets hit by everything as well. Your graveyard-based combo is operating in the same format players are over-preparing against Living End decks. Your combo also needs to loop Mox Amber and Mishra's Bauble, 0 mana spells that get tagged by Chalice of the Void, Void Mirror, and Lavinia, Azorius Renegade, all cards aimed at stopping Cascade.
Your artifacts are also at risk against anti-Hammer Time cards like Force of Vigor. Dress Down is a frequently used main and sideboard card for Shadow decks that kill off all of your Saga tokens and turns off Thassa's Oracle. The static ability on Karn, the Great Creator may also cause some issues if you don't have a bolt at the ready.
These are all pretty substantial barriers for the deck, and on paper, it sounds like an uphill battle. In a way, it is. However, the more sideboard cards your opponent brings in against you, the more they dilute their own game plan.
Depending on what hate pieces they have, you can pivot to a backup plan and beat down with creatures, or use your "anti-interaction" interaction to unlock your combo kill. A well-timed Brazen Borrower or Teferi, Time Raveler can deal with a Nihil Spellbomb, Leyline of the Void, or Pithing Needle once you're ready to go off.
What's in the Box?
Overall, I really liked the Grinding Breach deck. My draws were smooth and my plays were powerful. Even in games where I felt behind, I had several outs to win. I would absolutely recommend bringing this deck to either a local event or a larger-scale tournament. I'll continue to tinker with the archetype and find ways to either improve or side-grade. You'll be able to keep up with any developments by following me on Twitter at @AdamECohen. I'll catch you all next week!