Detain in MTG: Rules, History, and Best Cards

Last updated on February 28, 2024

Lavinia of the Tenth | Illustration by Willian Murai

Return to Ravnica introduced five new mechanics to Magic: The Gathering, one for each of the ally-colored guilds featured in the set. Designers were determined to get Azorius () right this time after the huge air-ball of a mechanic that was forecast. Unfortunately, they landed on detain as the best new mechanic. While flavorful, the detain effect has mostly been forgotten by players over the years, and indeed, was forgotten by them in 2012, too.

What made detain so reviled? What’s the flavor behind it? Is there any way to build a fun deck around it? Today, we’re digging into one of Magic’s worst mechanics. Strap in and let’s go!

How Does Detain Work?

Azorius Arrester | Illustration by Wayne Reynolds

Detain is a keyword action that stops a permanent from attacking, blocking, or activating abilities. Think of it like a one-turn Arrest or a Faith's Fetters without the fun.

The History of Detain in MTG

Detain was introduced in Return to Ravnica (RTR) in October of 2012. RTR featured the five ally-colored guilds – Azorius, Rakdos, Golgari, Izzet and Selesnya – and introduced new mechanics for each of them. Detain was the Azorius mechanic, meant to represent the league of cops and peacekeepers enforcing the law on Ravnica.

Nine detain cards were printed in RTR, with two more appearing in Dragon’s Maze later that block.

Detain is considered one of the lowest-power mechanics from a Ravnica set, as its narrow applicability means it needs to appear on valuable creatures and permanents. I doubt we’ll see it return, unless it’s costed much more aggressively.

Detain existed in a Standard environment where there were just better options for thematic mechanics. Selesnya decks of the time were busy populating Armada Wurm tokens while Izzet decks had access to Cyclonic Rift and Mizzium Mortars. What’s more, the best abilities around in the 2013 Standard environment were all triggered abilities – Blood Artist was still a menace from the Innistrad block, Prime Speaker Zegana didn’t care about attacking, and Boros Reckoner combo decks didn’t even glance at its first strike ability.

Indeed, it seems like the designers of detain didn’t take its environment into consideration at all, or at least assessed the meta incorrectly. There were basically no relevant targets for any detain ability, and the best ones were often overcosted for their effects. Sure, New Prahv Guildmage can shut down Vraska the Unseen, but do you really want to sink 5 mana into that effect every turn? There are better ways to deal with a planeswalker, especially in RTR. Try Detention Sphere!

Even Lavinia of the Tenth is underwhelming, despite supposedly being the tip-top of what detain can do. Stopping your opponent from activating that planeswalker for just one turn just isn’t worth it at 5 mana. You’d need a way to flicker Lavinia over and over to make it worthwhile.

Detain vs Summoning Sickness

Detaining a creature is not the same as giving it summoning sickness. Summoning sickness prevents the creature from tapping or being declared as an attacker on the turn it comes under your control (absent haste), while detain prevents a creature from attacking, blocking, or activating its abilities. A Royal Assassin can’t tap the turn it arrives, but you could activate Air Servant immediately once it resolves. Neither of these creatures would be able to use their activated abilities if they were detained.

Does Detain Tap?

Detaining a creature does not tap it. While it suffers many of the downsides of being tapped, the creature is still technically untapped. Keep in mind this doesn’t mean it can tap to activate any abilities.

Does Detain Stop Mana Abilities?

Detain does shut down mana abilities! A land or creature with an activated ability (shown as [cost]: [effect]) can be silenced by a detain effect. This means you can target a Llanowar Elves with Azorius Arrester’s triggered ability and prevent your opponent from ramping on the following turn.

Note this also technically applies to lands, but there are currently no detain cards that can target a land permanent. Makes sense: How are you supposed to arrest an Island? They don’t make handcuffs that big!

Does Detain Stop Planeswalkers?

Detaining a planeswalker does prevent it from activating any of its loyalty abilities. Loyalty abilities are activated abilities, so they’re shut down while the permanent is detained. Keep in mind a planeswalker’s static abilities will still be in effect, so a card like Sorin, Vengeful Bloodlord will still grant lifelink to your creatures and planeswalkers while detained.

Does Flicker/Blink Stop Detain?

Flickering a permanent that’s been detained does stop the detain effect. The game treats the blinked/flickered creature as a new object that wasn’t targeted by the detain effect earlier.

Does Giving Protection Stop Detain?

Giving a creature protection post-detaining does not remove the detained effect. However, a creature with protection from the detainer will be unaffected by the detain, since it can’t be targeted. Lyev Skyknight can’t detain a Black Knight, for example, but could detain a White Knight and it would remain detained even if it was given protection later on that turn by Brave the Elements.

Gallery and List of Detain Cards

• Archon of the Triumvirate
• Azorius Arrester
• Azorius Justiciar
• Inaction Injunction
• Isperia's Skywatch
• Lavinia of the Tenth
• Lyev Decree
• Lyev Skyknight
• Martial Law
• New Prahv Guildmage
• Soulsworn Spirit

Best Detain Cards

With such a small card pool and such a low ceiling on power, it’s not surprising detain doesn’t have many popular cards. The best, by far, is Lavinia of the Tenth. Lavinia is the closest thing to a detain boardwipe – pacifying all of your opponents’ nonland permanents with mana value 4 or less, all while being a 4/4 with protection of red for just 5 mana. As the legendary Azorius maze runner from Dragon’s Maze, it’s no surprise they tried to make Lavinia as strong as possible with the detain theme, but they still lack a lot of firepower.

Against decks without a focus on permanents (say, an Izzet burn deck built around Guttersnipe), Lavinia and the detain cards tend to whiff and just become overcosted creatures with no valuable upside.

Decklist: Juvenile Detention Center

Detention Sphere | Illustration by Kev Walker

I want to start this example deck guide by apologizing: I’m sorry about detain. I also want it to be good so bad! The Return to Ravnica Azorius intro pack was one of my first Magic purchases back in high school, and I remember running and being crushed over and over again by any other deck with the slightest hint of synergy. That said, I’ve put my years of losing experience to good work and created a franken-Azorius detain deck. Note that this deck is format-agnostic. Technically it’s legal in Modern, but it has a very low power level compared to contemporary Modern decks.

This deck heavily depends on your opponent running a creature-based deck. It’s very swingy in that a match-up against a spellslinger deck will spell your end, but it's a silver bullet for aggro decks.

To control the board, we’re looking to play our Azorius Arresters as soon as our opponent has a creature to target. To maximize the effectiveness of our detain mechanic, we’ll use Ephemerate and Cloudshift to flicker our Arresters and Azorius Justiciars over and over to keep the board locked down.

We’ll maintain control into the late game once we run out of Cloudshifts with Conjurer's Closet, before topping off our curve with Archon of the Triumvirate.

We’re leaning into the “detain nonland permanent” cards over the solely creature-targeting ones because of the wider application of their abilities. Chances are not every opponent will be running mono-red goblins, so we’ll want options to mitigate the effects of those noncreature permanents.

This deck might perform well at your kitchen table Constructed matches, but don’t expect to take it to Modern night and perform well. It’s a thematic deck using as many cards from Return to Ravnica as I could fit in, and it’s definitely fun to play, just not very powerful by any competitive standards.

Wrap Up

Inaction Injunction | Illustration by Wayne Reynolds

Wizards’ search for the perfect Azorius mechanic has been a learning experience, to say the least. Forecast and detain were mostly whiffs without much-staying power, and the newest Ravnica Allegiance ability addendum is just OK. Some day, I hope to see an Azorius themed mechanic that doesn’t stink, but for now we’ve got to make do with what we’ve got.

What do you think about detain? Were you ever able to make much use of it? How would you modify the mechanic to be more useful? Let me know in the comments, or over on Draftsim’s Twitter/X.

Thanks for reading, and stay out of trouble!