5 Kobolds & Catacombs cards that could be the next big sleeper hit

Without exception, in every Hearthstone expansion there are cards which end up becoming major players in the meta that almost no-one saw coming. These are your Dr. Booms, Mysterious Challengers, Grim Patrons, and—most recently—Prince Keleseths of the game. Previously, I predicted that Finja the Flying Star would be one such sleeper card, which I’m proud of in retrospect. So let’s see how I can do in that department again, on the eve of Kobolds & Catacombs' North American release. I can't promise guaranteed success, but there's definitely some juicy potential in the cards I've picked.

If you look back at the list of previous sleepers, there's a clear pattern in terms of what cards get undervalued: first, they (a) have high ceiling effects in terms of power and (b) they have conditional effects. People thought Boom was bad because he was weak to Big Game Hunter and the Bots needed to high roll damage. They thought Challenger was bad because filling your deck with Paladin secrets was bad. They knew Keleseth was good but everyone (myself included) assumed the lack of other two-drops in your deck was too big a price to pay.

With those precedents in mind, let’s browse the Kobolds & Catacombs collection looking for three key factors for the next big sleeper card:

  • It must have a conditional effect
  • The upper-limit on that effect has to be powerful
  • Players don’t think it’s very good currently (or are at least underrating it)

These are the strongest contenders I've found so far...  

Lesser Mithril/Emerald Spellstones 

I’m going to group these two together because they both accomplish basically the same task: putting bodies on the board. They are also cards people don’t seem to have talked up a ton because of the classes they belong to: Hunter and Warrior. Neither are exactly in the best state right now, and Secret Hunter isn't even Rexxar's strongest archetype. Both also have a similar conditional effect: you need to be holding each card in your hand and meet another requirement before it upgrades. 

But when they do upgrade, boy do those get powerful. Seven mana for 10/10 in stats across two bodies is Bonemare levels of broken, and 15/15 for seven doesn’t require any further analysis. Comparable power level exists at the five-mana slot for 9/9 or 12/12 in stats. That’s a very high ceiling of raw power for cost.

Now yes, the obvious counterpoint is, "But what if your opponent has a board clear, aren't you just sad?" To which the answer is: yes, of course you are. But the converse is equally true: if your opponent has just used their big board clear, these cards offer incredible reload value for a single card. And if they don’t have the clear? Prepare to do some serious damage. For an idea as to where these cards might go, here’s a sample list for both Warrior and Hunter. In fact, that Warrior list brings me to my next choice…

Spiteful Summoner 

A card similar in nature to Faceless Summoner from Whispers of the Old Gods, which did see some play, Spiteful Summoner gives you a random minion based on the cost of a spell in your deck. To abuse this card properly, you need to include very few low-cost spells so you're guaranteed to pull something more unfair with regularity. 

Enter the naysayers who will say that low-mana spells are often quite good (which is true), so if you want to meet the condition in a powerful way regularly you need to cripple your deck (which may not true, as per Prince Keleseth). 

In that regard, this card is clearly not meant for every class. But if you examine the Warrior deck I linked before, you’ll notice that the seven-cost spellstone is the only spell in the deck, meaning you’re getting a 4/4 with about an average of a 6/6 or so summoned alongside it. Again, 11/11 of stats for only six mana is unfair enough to see play. Yes, sometimes you'll hit Lynessa Sunsorrow or Silver Vanguard and be sad (again), but most of the possible rolls are pretty strong. 

Another class I could see this card seeing play in would be Paladin, which also doesn't need to run cheap spells and can therefore rely on a consistently powerful Spiteful Summoner. Spikeridge Steed is already a good card that works well with the Summoner, and several potential 8-cost spells present options as well. I opted for Dinosize in my list, though I’m unsure if sure it's good enough. Unfortunately, Summoner’s potential is handicapped somewhat by the inclusion of Call to Arms, but I think that card is just too good not to play and, and even if that's what your Summoner pulls, a random 4-drop isn’t totally unreasonable. 

"Oh hi, Flamewreathed Faceless." 

Arcane Tyrant 

I’ve said it before and I’ll say it again: free mana is always something to keep your eye on. The last "free" minion we saw was Happy Ghoul, and after some early Warlock shenanigans from J4ckie, it ended up flopping. This has led some to write off Arcane Tyrant too soon. "Happy Ghoul part 2? Hard pass." After all, you need to have an expensive spell and Tyrant in hand at the same time, and even then you’re only getting a 4/4—and how good is that, really? 

To answer that question, it’s very good. 

Again, the condition on this card isn’t easy to meet in every class, but it's much easier to meet than that of Happy Ghoul, especially in Druid. Do you think Nourish, Spreading Plague, and Ultimate Infestation were good cards already? Well, some percentage of the time they now come with an extra 4/4 body (especially when casting UI and drawing five. The odds of hitting one or more Tyrants are pretty high). I used a Big Druid shell to illustrate the point, but it works equally well in Jade lists which run all the same expensive spells.  


I’m going to take a big risk on Temporus and say that it has the potential to be better than people think. Right now, most people think that at worst its effect will lose you the game on the spot, while when it works it will be a "win more" card. And in many respects, they aren’t wrong. Giving your opponent two turns is a big deal. As such, you would only want to play this card when you were ahead. But if you’re winning anyway, why bother taking the risk? Hence "win more". 

I have a different take on the card. I see it as a "win if you don't lose" card. The distinction here is important, and this is what I have in mind: Priest has access to—and will probably play—Divine Spirit/Inner Fire combos in dragon decks. If you can take two consecutive turns, this enables you to set up a minion and then burst kill your opponent without giving them the opportunity to do anything about it. Temporus gives you those two turns. 

But how do you survive your opponent’s own double turn? By playing Temporus against decks that have a lot of trouble pressuring you sufficiently: the slower, control decks of the meta. Perhaps something like a Raza Priest before it finds its combo. If they don’t have access to their burst damage immediately after you drop Temporus, they die to your combo and there’s nothing they can do about it. It’s a card that can effectively negate every removal spell in the Priest’s arsenal, and that’s a big deal too. 

Even against aggressive decks where you’re probably not going to want to play Temporus, it’s still not that bad sitting in your hand as a dragon activator. Not great, admittedly, but not the end of the world. While Temporus may not end up breaking the meta, I think it may see more serious play than currently expected.

Final thoughts... 

While I do have a lot of other thoughts on what cards will be good this expansion (which you can see in my full prediction sheet), overall I am both excited and nervous about the cards coming tomorrow. Blizzard seems to be making some bold design decisions with respect to the potential power level of a lot of cards. Many of these are 'build-around' cards, including those listed above, which make for exciting deckbuilding challenges and interesting interactions. However, many also come complete with high potential power levels, and run the risk of breaking the meta. Time will tell, but Kobolds & Catacombs is one of the most exciting sets I’ve seen in a long time. 

Let me know which card you think the community is sleeping on in the comments below.