Block Monsters and How We Avoid Them

Posted in Play Design on January 5, 2018

By Melissa DeTora

Melissa is a former Magic pro player and strategy writer who is now working in R&D on the Play Design team.

Welcome back to Play Design. This week I'm going to be talking about steps Play Design takes to avoid "block monsters"—a term we use to describe decks wherein all the components come from only one block. When the majority of a deck comes from only a single block, it can create an unhealthy environment, especially when the deck is more powerful than the cards that are released after it. In Play Design, one of our goals for a healthy Standard is to create a diverse metagame. If a block is too strong, a block monster deck will dominate a metagame, and will do so until that block rotates. The existence of a deck like that can cause a stale tournament environment.

Here are two examples of block monsters—they are from very different times, but both of these decks followed similar patterns and caused similar problems.


When Mirrodin was released in 2003, the first Standard tournament of the season was States (RIP States). States was always a tournament that I looked forward to because it was the first chance you got to play with the new cards, so it was an exciting time for brewers. I remember my playgroup was working on an affinity deck with four of each artifact land, every card that said "affinity" on it (Frogmite and Myr Enforcer were givens, but we also tried cards like Scale of Chiss-Goria). The all-star in the deck was Broodstar. Long story short, this deck performed well enough at States that players began taking interest in it and iterating on it to find the best version. By the end of Mirrodin season, this was a tier 1 deck.

Then, enter Darksteel. Affinity got some new tools such as Skullclamp, Arcbound Ravager, and Æther Vial. When the introduction of a new set makes an already tier 1 deck significantly stronger, problems are likely to occur. Affinity dominated the format, despite the many answers to artifacts that existed in the same block. It was a one-deck metagame, and Standard was clearly suffering. Wizards of the Coast took action and banned nine cards from the deck.


Energy is a parasitic mechanic (a mechanic that only works with itself, doesn't need support from cards without the mechanic, and only exists in one set or block). The energy mechanic doesn't enhance your existing decks, but instead tells you to build a new deck using only energy cards. Most of the time, parasitic mechanics are healthy, because you still need support from other blocks. For example, mana bases and removal spells are usually not tied to a mechanic, so you'll have to go to other sets or blocks to fill out your deck.

However, that isn't the case with energy. Aether Hub and Attune with Aether provide strong mana bases while also enhancing your energy cards. Confiscation Coup and Harnessed Lightning are great removal spells for your energy deck, and there's no reason to play non-energy-producing removal spells like Lightning Strike or Abrade.

In Kaladesh, energy was a strong deck. When Aether Revolt was released, the deck got some significant upgrades, in the same way that affinity did years ago. Players iterated on the deck over time and got to where we are today. Now, the deck is one of the strongest in the metagame and dominates premier events.

How Play Design Avoids Block Monsters

The Play Design team didn't exist during Kaladesh development. However, we do understand the mistakes from Kaladesh block and actively try to avoid the situations above. One of our goals is to create an environment where the metagame changes over time. If all the strongest cards come from only one block, they will all rotate together, and the deck will either be too weak and not show up or be too strong and create a block monster. Block monsters cause less churn in the environment, and players are less likely to innovate and brew. If power is spread out among sets, we are more likely to create churn in the metagame. Here are some of the ways we do this.


Seeding is a term we use that means enhancing a future mechanic in a previous block. One example in which we seeded cards was for Ixalan. A tribal focus is a parasitic mechanic. Tribal decks are very unlikely to play cards outside of the tribe, so we wanted to seed tribal cards in Kaladesh block so players had options from different sets. Kari Zev, Skyship Raider; Gifted Aetherborn; and Yahenni, Undying Partisan were all given certain creature types with Ixalan in mind.

It's not always possible to seed cards in previous sets. Neither Merfolk nor Dinosaurs appear on the planes of Kaladesh or Amonkhet, so it was not possible to include them there. Dinosaurs are a rare tribe and would look pretty odd on Kaladesh or Amonkhet. Merfolk could have made sense in those worlds, but they were a late addition to Ixalan design. By the time that tribe was added, the worldbuilding in the previous year was complete. It was too late to rebuild the world to include Merfolk.

When we seed cards in previous years, it means that when Standard rotation occurs, decks will naturally lose cards. That leaves room to add cards in future sets. For example, when Kaladesh rotates out next year, a Vampire deck will lose Gifted Aetherborn and Yahenni, Undying Partisan. This gives us room to add Vampires to the fall 2018 set and beyond. The Play Design team is actively keeping an eye on when decks rotate, what cards they lose, and what holes they'll have after rotation. We then design cards in the next year's blocks to fill those holes, which will not only cause the previous year's deck to evolve, but also cause new decks to emerge.

Distributing Power

Sometimes it's not possible to seed (see the Merfolk and Dinosaur examples above). When we can't seed cards for certain decks, we will distribute the deck's power throughout the block or even the whole year.

With Ixalan, we did not put enough power in all of tribes to create a competitive Standard deck. If we did that, we'd be very likely to see a similar pattern that we saw in Mirrodin and Kaladesh blocks. If the tribes in Ixalan were stronger than we had anticipated, then when Rivals of Ixalan came out we could have had a tier 1 block monster.

Mechanic Percent of Power in Set 1 Percent of Power in Set 2
Energy 100% 50%
Affinity 100% 50%
Vampires 75% 25%
Merfolk 50% 50%

This chart is an example of what could happen if we add too much power to a block. For energy and affinity, we had complete decks in the first set of the block. In the second set, power was added to both decks. Since the decks were already strong after set one, they became too strong when they were powered up further in set two.

For the Ixalan tribal decks, there weren't enough powerful cards to create a tier 1 deck in the first set. If Vampires is about 75% of a deck and Merfolk is about 50% of a deck in Ixalan, there is plenty of room for powerful cards to be added in Rivals of Ixalan. While the tribal decks will still rotate all at once, the power is distributed across the block instead of everything appearing in the first set.

In the real world, the tribes were not strong enough with only one set's worth of cards, but we added some power to the tribes with Rivals. Vampires was the closest tribe to competitive Constructed–viable and did show up at Pro Tour Ixalan as a mono-white deck. The Vampire and Merfolk lords add significant power to the tribes, and I'm looking forward to seeing how the real world will approach these archetypes.

That's all for this article! I hope you've enjoyed the Rivals of Ixalan previews this week. If you missed any of the cards, or just want to see the whole set in one place, head over to the full Card Image Gallery.

Also be sure to check out the Rivals of Ixalan Pre-Prerelease beginning at 11 a.m. PT today (January 5) on I'm sure it will give you a great sneak peek at what you can expect from the Rivals Prereleases on January 13–14!

Until next time,

Melissa DeTora

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