Everything you need to know about Hearthstone's Boomsday expansion

The Boomsday Project is the second expansion in Hearthstone's Year of the Raven, following on from the spooky shenanigans of The Witchwood. This time around, the set's 135 cards are themed around dangerous experiments being conducted by Dr Boom (who you may remember) inside his Netherstorm laboratory. The expansion contains several new keyword mechanics, plenty of crazy powerful cards, and some brand new singleplayer stuff. For this piece, I've wrapped up everything else you need to know about The Boomsday Project, starting with…

When does The Boomsday Project release? 

The Boomsday begins going live across Blizzard's regions on Tuesday, August 7th. Here's the official rollout schedule, direct from Blizzard:

  • Europe: 7 August at 19:00 CEST
  • Americas: 7 August at 10:00 PDT
  • Asia: August 8 at 02:00 KST (01:00 CST)
  • China: August 8 at 06:00 CST

The best way to keep up with what's happening on your local server is by following the official @PlayHearthstone Twitter account.  

What's the best way to buy packs? 

Assuming you're not sat on a mountain of in-game gold or Arcane Dust to craft the cards with, this might be the most important question of all. As usual, Blizzard is offering a Pre-Purchase option for Boomsday, only this time, they're actually offering two options. Both break down to about $1 per pack, but each comes with different bonuses, depending on what interests you.

For $49.99 you get 50 packs to open on Tuesday, August 7th, as well as a Mecha-Jaraxxus card back, and a random Golden Legendary card from the set.

For $79.99 you get the Boomsday Project Mega Bundle, which gives you 80 packs to open, the Mecha-Jaraxxus card back, a random Golden Legendary card from the set, and the Mecha-Jaraxxus warlock Hero.

One neat caveat is that you can actually purchase both packs if you desire, allowing you to technically get two Pre-Purchase bundles (for 130 packs and two Golden Legendary cards total), whereas in the past you were restricted to the single offering. Post-launch it's also worth keeping an eye on Amazon Coins, which can often represent a discounted way to buy packs when a promotion is live.  

Finally, even if you're not planning to play immediately, be sure to log into Hearthstone after The Boomsday Project launches because for a limited time each player will receive three free packs and a random class Legendary minion (or Hero card) from the new expansion.

Where can I see all the cards? 

Blizzard's official site for the expansion has the lot, as you'd expect, and enables you to filter by class. For more detailed filtering, third-party resource sites like Hearthpwn and the Hearthstone Wiki are helpful. You may also be interested in this document, which contains power predictions based on a poll taken by Vicious Syndicate. Our resident expert has highlighted the cards he thinks are underrated in blue, and overrated in orange. 

Tell me more about that singleplayer content 

The past couple of expansions have been killing it on free single-player modes. Kobolds and Catacombs introduced Dungeon Run, while The Witchwood added more of the same via its Monster Hunt mode. Both of these delivered hours of fun as you battled unique bosses and played with powerful custom treasure cards.

The Boomsday Project is a little bit different. Instead of grinding your way through a dungeon, upgrading your deck along the way, The Puzzle Lab presents four types of problems to solve, each with their own objective:

Lethal, which requires the player to destroy the enemy Hero.

Mirror, which requires the player to create a perfectly mirrored battlefield.

Board Clear, which requires the player to clear the battlefield of minions.

Survival, which requires the player to survive the enemy Hero Power.

In total there will be more than 100 puzzles to beat. Complete them all and you’ll end up facing off against the not-so-good doctor himself. Defeat the villainous scientist and you’ll be awarded the Boomsday! card back. The Puzzle Lab will release on August 21st, two weeks after the expansion drops, presumably so we don't spend all our time with it immediately, rather than crafting new decks to try on ladder.

What new types of cards are there in The Boomsday Project? 

Omega Agent

CCG expansions often focus on 'cycles' of cards, which are variations on a new idea. In Journey to Un’Goro we had the Quest cards. In Knights of the Frozen Throne each class received a Death Knight. Kobolds and Catacombs had Legendary Weapons. The Boomsday Project actually has several cycles, including Omega and Project cards.

Omega cards, such as Omega Agent, are cards that you can play early in the game at their printed rate, but will do something extra if you play them once you reach 10 Mana Crystals. This is a rewarding mechanic that gives Omega cards additional flexibility, but sometimes at the cost of the 'vanilla' version being somewhat underpowered. 

The best part about them is that there's no penalty for gaining the additional effect once you're at 10 Mana. The idea is that these are cards which are fine, but probably not amazing, if played early—but will be borderline OP if you can make it to the late game.

A more minor cycle are the new Project cards, which have a symmetrical effect—both players benefit from the card when it's played.  Project cards aren't a true cycle, because they only appear in four classes—Druid, Warlock, Mage, and Warrior—but the trade-off of sharing the card's effect with your opponent makes for some interesting deck-building considerations. 

For example, the Biology Project gives both players two filled Mana Crystals for the rest of the game, at a cost of a single Mana. This is a great deal for this kind of ramp effect, but you’re forced to weigh its value against giving your opponent the same benefit. Why play it? Well, in this instance the plan will be for the Druid player to build a deck that benefits more from the additional Mana by including expensive late-game cards.

What about some of the new Legendaries? 

Myra's Unstable Element

I heard you like drawing cards.

The Omega and Project cards aren’t the only new mechanics in The Boomsday Project. Get ready for the debut of Legendary Spells. Whereas Legendary cards were originally only minions, the rarity spread to Weapons in Kobolds and Catacombs with the likes of Twig of the World Tree and Woecleaver. Now, each class is receiving a Legendary spell, and as you'd expect some of them look very strong indeed. 

The Rogue Legendary spell is called Myra's Unstable Element, and will draw every remaining card in your deck for just 5 Mana. Perfect for adding extra gas into the tank of an aggressive deck that's running dry on resources. It won't matter if you go into fatigue, provided you can kill the opponent in the next couple of turns with all those cards.

Are there any new Hero cards? 

Dr Boom, Mad Genius

The infamous 'Dr. 7' returns. 

Yes, but only one. In the same vein as The Witchwood including Hagatha the Witch for the Shaman class, The Boomsday Project also contains a Hero who embodies the theme of the set. Warrior players will be able to include Dr Boom, Mad Genius in their decks, and when played he'll transform the current Hero and Hero Power. The new Dr Boom costs 7 (of course he does!) and provides an immediate boost of 7 Armor. 

The real reason you'll want to consider including the Doc in your deck is because he also grants all your Mech cards the Rush keyword thereafter, a substantial passive benefit not unlike how Frost Lich Gaina gives all Elementals the Lifesteal effect. Boom's upgraded Hero Power cycles randomly each turn between a number of options, several of which also have Mech synergy. Check out all the options below.

Are there any new keywords? 


The most exciting Magnetic card.

It wouldn’t be a new Hearthstone set without a sweet new mechanic, and 'Magnetic' certainly feels like has potential. Only Mech minions can have the Magnetic keyword, and it enables you to choose whether to “attach” the card to existing Mechs by playing them to the left of that unit, combining both into a larger minion, or play it on the right of as a regular minion. 

As you know, there are plenty of Hearthstone cards that care about the placement of your minions, so having to take this into account when you decide where to put your Magnetic minions should prove a decent challenge. 

Additionally, as you can effectively attack immediately with the stats you're adding to the board if you magnetize the new Mech to one that's already been on the board for a turn, it's almost like the new minion has charge or is a buff spell. But bear in mind the risk of choosing to magnetize is that the effect can then be removed with Silence. Plan your plays accordingly. 

What cards should I craft and where can I find hot new Boomsday decks? 

Flobbidinous Floop

At last, some help for Druid.

Strongly resist the urge to craft anything Epic or Legendary on a whim for the first couple of weeks. Bear in mind that the meta will be incredibly unstable, and what might seem S tier initially will be tomorrow's dumpster deck. 

That said, the legendaries which look the safest crafts include Flobbidinous Floop, which is almost bound to be OP for Druid, The Soularium if you like Zoo Warlock, and Zilliax if you have any intention of playing a Mech deck. Electra Stormsurge is also likely going to be an absolute staple in Shaman, so worth it if you plan to play the class at any point in the next two years.

Alternatively: craft whatever you want. PC Gamer is not the boss of you.

 As for decks, if you’re looking to find the initial Boomsday Project hotness, good places to start are sites like Hearthstone Top Decks or the HS Pro Decks Twitter feed. Vicious Syndicate also has a list of 20 decks to try on day one, while the Competitive Hearthstone subreddit is always an excellent repository of findings from serious-minded players. If you’re interested in trying your hand at something spicy, we’ve got a helpful guide to get you started with nine degenerate Boomsday Project combos. And of course, if you want to see new brews being tested live, the Hearthstone Twitch directory will be a fun place to hang out for weeks after launch. Keep a particular eye on what Savjz, Dog, Kibler and Firebat are up to.

Anything else I need to know?

Remember to buy packs from the right expansion! That covers most of it, for now. We'll add new info, including some of the best early decks, as it arrives. We’ll also be updating our 20 Best Legendary Cards, as picked by pro players, once the meta settles. Let us know in the comments what deck you're planning to build first, which Legendary you're most excited about, and how your own mad science works out.