Boast in MTG: Rules, History, and Best Cards

Last updated on February 13, 2024

Eradicator Valkyrie | Illustration by Tyler Jacobson

The plane of Kaldheim takes heavy inspiration from Norse mythology. During the times of the Norse, stories of great battles would sweep through the lands by word of mouth. Warriors would boast of their great achievements as they sat by campfires over food. To incorporate that same flavor into Kaldheim, we have the boast mechanic.

So let’s take a look at this mechanic and how it carries over mechanically to the game of Magic.

How Does Boast Work?

Usher of the Fallen | Illustration by Anastasia Ovchinnikova

Once per turn, you can activate the boast ability if you attacked with a boast creature. Once you activate the boast ability a trigger goes on the stack with the ability and resolves like any other activated ability. You can activate boast at any time during your turn after attacking with a boast creature, including in the declare attackers’ step before blocks.

The History of Boast in MTG

Boast only appears in 2021’s Kaldheim. Since it only appears in a single set, all the cards with boast came out at the same time. Since Kaldheim is so recent there hasn’t been a lot of opportunity for any new sets to have boast so it can’t be considered evergreen.

Can You Activate Boast as an Instant?

You can boast at instant speed, or whenever you have priority after declaring a creature with boast as an attacker.

When Can You Boast?

You can boast any time after the declare attackers’ step as long as you attacked with a creature with boast.

Can You Activate Boast Before Blockers? Before Damage?

You can activate boast before or after blockers, as long as it’s before damage. Any time you have priority after a boast creature attacked you can activate boast.

What About After Combat?

You can boast after combat, assuming the creature with boast survived. There are no timing restrictions to boast other than it has to happen after attacking with that creature, and it can only happen once per turn.

Can You Boast Twice?

You can only boast once per turn. But Birgi, God of Storytelling allows you to boast twice in a turn rather than just once.

Can You Boast with a Creature that Was Put onto the Battlefield Attacking?

Since the creature was put onto the battlefield attacking, it was never declared as an attacker. You need to declare a creature with boast as an attacker to activate boast so you can’t use boast on a creature that entered attacking.

If You Get Multiple Combats, Can a Creature Boast Twice?

Even if you gain multiple combat steps, you can only boast once.

How Do You Activate Boast in MTG Arena?

You can click on your boast creature after attacking with a creature with boast and pay any costs to activate the boast ability. Activating boast works like any other activated ability on MTG Arena.

Gallery and List of BoastCards

• Arni Brokenbrow
• Axgard Braggart
• Battershield Warrior
• Dragonkin Berserker
• Draugr Recruiter
• Duskwielder
• Eradicator Valkyrie
• Fearless Liberator
• Fearless Pup
• Goldmaw Champion
• Hagi Mob
• Horizon Seeker
• Tuskeri Firewalker
• Usher of the Fallen
• Varragoth, Bloodsky Sire

Best Boast Cards

There aren’t too many multiformat all-stars with  this mechanic since there’s a limited number of cards with boast. The best mythic and rare are both worth mentioning, but neither made much of a splash. Still, let’s look at the “best” boast cards and maybe one day they’ll find a more concrete home.

Dragonkin Berserker

The strongest boast rare, Dragonkin Berserker threatens to quickly take over the board by acting as an aggressive 2-drop that creates 5/5 dragons with boast. If you already have a dragon then the boast ability (and all other boast abilities) become cheaper. While it’s hard to expect this card to place highly in Standard, it was a powerhouse in Limited that could win the game by itself.

Dragonkin never found footing as an army-in-a-can type card in the way cards like Dragonmaster Outcast did in control decks of the past since it needs to attack and survive. It also never found a home in aggro decks since it didn’t have haste, an overly impressive stat line, or an enter-the-battlefield ability so opponents could easily contain its strengths.

Eradicator Valkyrie

The boast mythic, Eradicator Valkyrie is a 4/3 flying, lifelink, hexproof card that reads like it should see consistent play. Add in the boast ability that you can sacrifice a creature to force your opponent to sacrifice a creature or planeswalker and it looks like a powerful card. Even though the power level is there, this Valkyrie never found much of a home.

Usher of the Fallen

The only boast card to see consistent Standard play, Usher of the Fallen helped create multiple strong mono white aggro decks that tried to keep cards like Alrund's Epiphany in check. While ultimately both Epiphany and Faceless Haven saw bans, Usher continues to play a role in white aggro decks.

Wrap Up

Dragonkin Berserker | Illustration by Lie Setiawan

Boast is a mechanic that played out well in Limited. While it didn’t move the needle much in Standard, Pioneer, or Modern it certainly has room for further exploration in the future. Mechanics that incentivize attacking can lead to faster games, but these abilities costing mana help to keep them from snowballing too fast. While that makes them more balanced in Limited, it also tempers my excitement for future boast cards shacking up Constructed Magic unless the ability or cost is pushed aggressively.

Overall, my opinion of boast is much like listening to the same story too many times: it has potential for enjoyment, but it’ll feel like a disappointment once you’ve seen all the tricks.

What do you think of boast as a mechanic? What kind of abilities you think WotC could print to create a viable set of boast cards for multiple Constructed formats? Are you looking forward to more boast cards in the future? Let me know in the comments down below or over on Draftsim’s Twitter.

Thanks for reading and stay safe.