Mono-Red Prison Is Better Than You Think In Modern

The banning of Arcum’s Astrolabe in Modern has allowed Blood Moon and friends to rise again! Todd Anderson breaks down the new Mono-Red Prison.

Blood Moon, illustrated by Franz Vohwinkel

Mono-Red Prison is often a deck I despise playing against. The idea of getting locked out of casting spells is terrifying for someone who so frivolously and frequently sleeves up Serum Visions. Chalice of the Void is likely a card I would “unprint” if I could, just deleting it from existence. The same goes for Blood Moon.

But damn y’all, I get it now. I really do.

For the longest time, I just wouldn’t play any of these types of spells because they didn’t really mesh with my playstyle and I honestly didn’t think I’d enjoy locking folks out of the game. Turns out it’s really fun for one person: the one controlling the lock piece! After playing with all sorts of decks on stream, Prison has just become “another thing” I try from time to time, and I gotta say that I’m really digging Mono-Red Prison at the moment, though I doubt my thinking on the archetype will mirror conventional wisdom.

It’s no secret that the Legacy version is much more powerful. Having multiple lands that tap for two mana creates some outrageous starts revolving around Chalice of the Void, but it also just allows for more explosive three-drop threats. In Modern, the threats you have access to are similar, but the lack of Ancient Tomb and City of Traitors means those fast Goblin Rabblemaster starts aren’t nearly as reliable or consistent. Plus it certainly doesn’t help that Modern has a lot more creature removal running around, making those early threats much less impactful.

Today we’ll examine a few different Modern builds of Mono-Red Prison and explore some options that might not be considered “stock.” As we explore these options, I just want you to know that I haven’t become “the Blood Moon guy.” I still like casting Archmage’s Charm, but I like to test out some of the more rough and tumble strategies. One can only get rekt by Veil of Summer so many times before you stop casting Fulminator Mage.

Let’s start with a build I tried earlier this week, from one of the format’s premier Mono-Red Prison pilots, and discuss the cards chosen in this build and what I like/dislike about them.


Abrade has been a boon for Red decks since it was printed. I can’t tell you how much Abrade’s versatility gives me “the giddies” when it comes to red interaction. I love variable-use cards and especially so when those cards are efficient at answering things for their cost. Abrade starts to look like a “Red Charm” in some respects. The fact that it costs two mana is actually a benefit here, as it dodges your own Chalice of the Void while providing you with some versatility for the extra mana cost.

Blood Moon

An obvious inclusion, and the premier reason to play the deck. If you play this archetype on the regular, you know it’s only good so long as Blood Moon is. There are times when you need to give up the ghost, but right now is not that time. The banning of Arcum’s Astrolabe made Blood Moon much more punishing.

Chalice of the Void

Another must-have. If Chalice of the Void is bad, your deck is no longer playable. Much like Eldrazi Tron, the strength of your deck is entirely reliant on whether or not Chalice of the Void is good. If both Blood Moon and Chalice of the Void are strong, Mono-Red Prison is great. If one of the two is good against the format, your deck can still be playable, though I wouldn’t exactly recommend it. At the moment, I think both are excellent.

Chandra, Torch of Defiance

Behind the lock pieces, Chandra, Torch of Defiance might be the best card in the deck. It slices, it dices, it picks the opponent apart with the flick of your wrist. Being card advantage, removal, and a stout win condition behind Ensnaring Bridge is a huge deal.

Karn, the Great Creator

Another hot one, and obviously a great inclusion for any archetype that wants to run Ensnaring Bridge. The loss of Mycosynth Lattice isn’t such a big deal here because you don’t actually have a ton of mana lying around. You burn Simian Spirit Guide and Desperate Ritual early to get Blood Moon and friends on the table, but then you’re left with two or three lands. Drawing three more isn’t exactly easy.

The toolbox kit that Karn, the Great Creator provides, as well as the additional Ensnaring Bridge, more than makes up for your inability to protect it with creatures or produce an extraordinary amount of mana to leverage the tutor factor. Both aspects are usually wanted/needed with a planeswalker that can’t protect itself, but Ensnaring Bridge does a lot of heavy lifting here.

Mazemind Tome

I’m not sold on this one yet. I feel like it might be a better version of Treasure Map, but is that even Modern-playable? I’ve seen it in a number of Urzatron decks, but I feel like those need scry because they’re trying to find very specific stuff by the fourth or fifth turn. This archetype feels a lot more like you should be trying to mulligan into a Turn 1 Chalice of the Void. You also don’t have the right removal package to utilize all those extra cards.

It’s flashy, and it’s certainly good, but I don’t think it belongs in this archetype.

Chandra, Awakened Inferno

I was pleasantly surprised how easy this was to cast…in Legacy. Without Ancient Tomb, Chandra, Awakened Inferno is just too slow, clunky, and unreliable in Modern. It’s also not even the knockout blow that it should be. Yes, it can close the game over time, but the sweeper effect isn’t perfect and the minus ability to kill an opposing threat isn’t exactly efficient. It does some wild things in certain spots, but I’m going to cut it from future builds.

Seasoned Pyromancer

This is one I can definitely get behind, though it does make for some awkward scenarios involving Ensnaring Bridge and 1/1 creatures. Sometimes it’s just impossible to fully empty your hand because you draw two lands from it! But most other times, it’s just a stellar blocker that turns dead lock pieces into actual resources and is one of the best topdecks in history.

Simian Spirit Guide Gemstone Caverns

I love Gemstone Caverns more than most humans on this planet. I often contemplate choosing to draw when it’s in my deck just so I can get the fabled “luck” counter. Since we don’t have Ancient Tomb, these two gems are all Modern has if we want to cast an early Chalice of the Void or Blood Moon. Some versions play more Ritual effects, adding Pyretic Ritual into the mix. They’re a bit more “all-in” than this one, but I think “all-in” is where you need to be.

Dragon's Claw

I found myself just never casting this card until I’d already gotten Chalice of the Void online. It’s obviously good against exactly Burn, but it’s not even that great against Mono-Red Prowess. If you don’t kill their creatures, the three to six life you gain before dying isn’t relevant. Ensnaring Bridge plus Dragon’s Claw can do some work, but you really just need to hope Chalice of the Void or Ensnaring Bridge is enough. I’d cut it.

Torpor Orb

Not enough decks have enters-the-battlefield effects for this to be playable. Not yet. Cards like this have people asking me all the time, “Hey Todd, should I bring this in against Stoneforge Mystic decks?” No. It’s a trap. It’s like Surgical Extraction. People see one creature with an enters-the-battlefield ability and lose their minds.

The rest of the tutor package, and even Anger of the Gods, felt good when I was playing the archetype. I’d leave virtually everything else alone.

Here’s what I’d play if I was going to sleeve up Mono-Red Prison in a tournament this weekend.


This card is a heater, but it’s also just incredibly versatile. I love cards like Abrade and Pillage in red decks because they give you flexibility. When you play a deck like Mono-Red Prison, having cards that are great at different points in the game for different reasons is huge. Pillage adds to our “mana taxation” by constricting their total mana. That in turn makes Chalice of the Void a bit better, but it also makes Blood Moon better when you blow up their basic lands.

Pillage is one card I’ve been highly impressed with, even though it doesn’t really do a ton in the games you play. It’s just good, and especially so when artifacts are running rampant. It will almost always have a viable, and valuable, target to blow up. I wanted Pillage in Modern for so long, and I’m glad they found a vehicle in Modern Horizons to reprint it without putting Stone Rain in Standard.

Chandra, Heart of Fire

Speaking of Pillage, it seems like we need a few more instants and sorceries to make this hot new card a bit stronger! It isn’t that difficult to get your planeswalkers up to ultimate status, and it certainly isn’t the flashiest of ultimates, but blowing up all your opponent’s artifacts or lands is quite good!

The upside is that both small activated abilities of Chandra are useful in a number of scenarios against a number of archetypes. See the pattern? I love these red cards that have multiple uses. That’s why I love burn spells as removal!

I don’t have much to say about Chandra, Heart of Fire just yet, but I do like the play patterns and overall power level. It isn’t dominating like some planeswalkers if left unchecked, but it can certainly get you out of some tight spots.

Welding Jar

I love this card, and I especially appreciate a free way to protect an Ensnaring Bridge in a pinch. I found myself often wanting a free artifact or two for Karn, the Great Creator, and Welding Jar can keep you safe in sideboard games. It’s so much better than it looks on paper, and such a unique effect. It’s hard to describe just how good it feels as a prison deck to tutor for Welding Jar when you really need one. Any mage who has cast Whir of Invention for X=0 in response to an Abrade knows exactly what I’m talking about!

Pithing Needle

The mana differential between Pithing Needle and Sorcerous Spyglass is huge. I found myself wanting a cheaper version just about every single time, as I needed to cast Karn and find the answer to the opposing planeswalker immediately. If you play something like this maindeck, having the extra information is handy, but if you’re tutoring for it, then you already know what you’re naming.

Alternatively, we could move in a different direction. Here’s something I want to try in the very near future. Notice there’s a “prison” element missing!

Bonecrusher Giant

This addition to the archetype isn’t exactly stellar with Ensnaring Bridge being “Plan A,” but it’s versatile and powerful in this build. We’re much more like Chonky Red from Pioneer, acting like a medium-sized beatdown deck with disruptive elements. I like getting a little more interactive, and Bonecrusher Giant is exactly the card to do that. It provides a reasonable body at a solid rate and gives you the chance to interact with an opposing creature.


An old favorite of mine, Glorybringer has really thrown its weight around in Modern as of late in the Gruul Midrange deck. I’ve enjoyed how hard it is to kill as well as the immediate value generated by haste killing a planeswalker on top of the ability killing a creature.

Things have gotten a bit more “on the battlefield” as of late, which means more creatures and more reason to play hasty Dragons. When games are longer and your opponents’ removal is worse thanks to Chalice of the Void and Blood Moon, stuff like Glorybringer can solve specific problems without being answered for small amounts of mana.

This version lacking Ensnaring Bridge is obviously a serious choice, but mostly I just want to see if creatures can be viable again. Bonecrusher Giant and Glorybringer are both a lot better when you need to be proactive, but neither answers something like Primeval Titan. It’s a conscious choice made between being a true prison deck and just skirting around the prison strategy. This iteration will likely play out more like Eldrazi Tron than traditional prison, using Chalice of the Void and Blood Moon as a way to protect your threats.

Rending Volley

Rending Volley is sweet because it’s a cheap removal spell that dodges your own Chalice of the Void. I was looking for a card that could help me out against random stuff like Merfolk or Humans while still being castable through Chalice of the Void. It’s possible you want something like Chandra’s Defeat or the more generic Flame Slash but Chalice of the Void is relevant enough against most aggro decks that you want your removal to be unaffected.

Goblin Rabblemaster

Overall, I feel like this version isn’t quite up to par just yet, but I like what’s going on. I need to figure out if Goblin Rabblemaster is worthwhile, or if I should focus on threats that are harder to kill. Goblin Rabblemaster is highly aggressive and can close games, but it’s only as good as how well you clear blockers out of the way. Without Ancient Tomb and friends, I doubt you can cast it in a relevant time frame or leverage the extra bodies.

I’ll be exploring quite a few different options over the next week as I explore this archetype further. My understanding of how the deck operates feels reasonable. I like the tutor packages but feel most sideboard builds could use some tuning up. The trick is making sure you have the right tools for Karn without cutting off access to “real” sideboard slots.

Sitting on your hands behind an Ensnaring Bridge is terrifying, but it’s especially hectic when your opponent has access to their sideboard. Almost everyone has some way to kill Ensnaring Bridge after sideboard, which means the first one is no longer “good” like it is in the opening game. Often you’ll have it killed and need to find another. That’s what drives me to push toward this more creature-oriented build. That, and playing against a bunch of control decks over the last few days!

If Mono-Red Prison is your style, give some of these decks a whirl and see how you like them. I really like the second build but I’m afraid that my love for Pillage and the new Chandra, Heart of Fire is blinding me to just how strong Mazemind Tome actually is. Regardless, Modern feels pretty open right now. Aside from a few annoying cards, the format is mostly reasonable with a nice helping of “diverse.” Banning Arcum’s Astrolabe feels like it’s been a net positive for the format, and I’m happy to explore it more!