Team 5 recently announced a number of nerfs designed to address the prominence of Druid in Hearthstone make a few other changes . To find out a little more about the thinking behind the adjustments, I caught up with senior designer Mike Donais and game designer Dean Ayala for a chat. (Be sure to check out the second part of this interview too, in which we dig into the design of the Death Knight hero cards .)

“ "One of the tools that we have tells us what the highest win rate draw/win cards are. So that means we can see that Innervate is one of the top three cards in Druid and has been over time." - Mike Donais.

The Fiery War Axe change.

“ "I talked to some pro players privately... and discussed what kind of changes they want exactly... and got some positive feedback." - Mike Donais.

“ "The current top four decks all got hit, so that means – what’s open now?" - Mike Donais.

“ "Innervate, more than anything, just limited Druid feeling any different set to set, which I think is one of the more dangerous things for the meta game in general." - Dean Ayala.

The change to Innervate.

“ "Our objective with changing Innervate wasn’t to take it from an A+++ card to just an A+ card, because both of those... still sort of fit in every deck." - Dean Ayala.

“ "As a team, we underestimated how good that card might be." - Dean Ayala.

Spreading Plague's new form.

“ "Increasing the mana cost doesn’t really take away from the cool aspect of the card, but still accomplishes the same goal." - Dean Ayala.

We do a lot of stuff. One of the first things we do is – we’re playing on the ladder every day, and we’re seeing a lot of Druid, that’s step one. And of course, we read Reddit and our forums, and it’s like ‘okay, people are playing Druid, people are talking about Druid, but not everyone’s complaining about Druid. Some people are complaining about Mage or Warrior or Paladin.’ So there’s always a mix. Whenever you go to the internet you’ll get basically every possible answer and every possible opinion.And then we start talking. We put up on the whiteboard some ideas, like ‘here are some good cards in Druid’. One of the tools that we have tells us what the highest win rate draw/win cards are. So that means we can see that Innervate is one of the top three cards in Druid and has been over time. We can see that – the other card we nerfed…Spreading Plague.Yeah, Spreading Plague.There are so many names internally that it’s hard to remember what we actually shipped with a lot of the time.That card, at one point, was called Unleash the Taunts, even though it doesn’t do exactly that. So Spreading Plague was the top card in Druid, which was kind of a surprise, but it makes sense if they’re having challenges with aggressive decks. Having that card helps you beat those match-ups. We looked at other cards. We looked at Ultimate Infestation. It was around the middle for the cards that were being played in that deck – like, the tenth best card? And for a ten mana card like that, there’s more to it than just the numbers, so we have to think about – how does it feel to play against? Is there some reason the data might be skewed because of the fact that it’s a ten mana card? Things like that. So we think about that too and take that into consideration. But that’s sort of how we got to where we got with the Druid cards.But at the same time we also cared about basic cards. This is something that was in my blog post . We wanted to make sure that the game overall didn’t contain something like 50% basic and classic cards. We wanted to get closer to 25-30%. If there’s basic, classic and six expansions, then basic and classic could be one seventh. I’m fine if it’s more than a seventh, but it shouldn’t be, like, three sevenths.So in our efforts to reduce that slightly we looked at basic cards, and we saw Innervate’s grade one, the other basic cards in Druid weren’t nearly as good in that deck, things like Swipe and Wrath, Wild Growth. And that’s how we got to the basic cards in the other classes at the same time. We know that [Fiery] War Axe has been in basically every Warrior deck forever, and it’s been very very strong. If you compare it to a card like Frostbolt, then it’s two mana for two Frostbolts almost. So super strong card and it’s also basic and it’s been around forever, and we knew that even if it was a bit weaker it would still get played a lot. We’ve seen other weapons, that were not as good as Fiery War Axe get play in classes that didn’t have Fiery War Axe, like Paladin and Hunter and Shaman. So, in our effort to reduce the basic and classic, we looked for those cards and that’s how we hit Fiery War Axe, and so on down the line.Well, when you put stuff out there you always expect every reaction on the internet. There’s some people who are like – hey, great, thanks, these are exactly the changes we wanted. In fact, Reynad made a video asking for Innervate to be nerfed a couple of weeks ago, so I’m sure he was super happy with that idea, and a lot of the players I talked to ahead of time – I talked to some pro players privately on Skype – and discussed what kind of changes they want exactly, and talked to them about very specific cards, and got some positive feedback, so I think once things calm down, people will be pretty happy, because these are things that people have been asking for. About a year ago Firebat did this awesome online tournament that he called the Firebat Invitational and it was really cool because he asked people what cards should they exclude, and the most voted-for card from today’s current Standard was Fiery War Axe.When we do set rotation we make a lot of changes. We rotate three expansion sets, we rotate the five or six cards that move to Wild, and that all happens at once and it creates a lot of change, and a lot of experimentation happens after that. It’s a really fun time in Hearthstone. And I think that having that happen halfway through an expansion is an advantage, it makes everyone have a lot more fun, experimenting, finding out what’s good again. The current top four decks all got hit, so that means – what’s open now? If all those decks lose 2% win rate and everything else below it goes up by 2% then that’s a lot of decks that will be around the same win rate, and people will have to find out what the best versions of those are, and then as they explore that, they can modify their decks to be good against the best ones, instead of being good against Druid.Yeah, it’s a great deck, and something that people have wanted to play for a long time, and explore it, and played it even when it was at a low win rate because it was a fun concept, so it’s nice to give people a chance to win some more games with it.I think some of the decks that are traditionally good against Kazakus Priest – or Razakus Priest – is the traditional control decks, like Control Warrior, and a lot of the decks that have been pushed out by Jade Druid, so we hopefully think we’ll strike a balance there where those decks will come back into the fold and be able to fight a little bit, because the Priest deck they’re playing right now is actually very strong, so I think if Jade Druid were to completely go away and the meta were to stay completely the same outside of that it might be just as powerful as Jade Druid is now. But the hope is that the meta shifts a bit, because maybe Jade Druid is played slightly less.A little bit, I mean, Innervate’s a good card with basically every card in Hearthstone. The things that it limits, more than anything, is that it means that Druid decks have two less cards that you can put in them. When a new expansion comes out, we’d like you to be able to play a lot of the old cards, and also a lot of the new cards, so I mean, when you have stuff like Swipe and we had Keeper of the Grove and Ancient of Lore, and if all those cards still existed, every Druid deck is 18 cards that you have to include because they’re so powerful, plus, maybe some stuff from the new set or maybe some stuff from the set before the latest set, and it basically feels like the same deck.I think ‘refresh two mana crystals’ is a reasonable card design to have in the game at some point. It’s something that we talked about, so obviously we don’t think it’s that far off. We think it has pros and cons. I think it’s easy to exaggerate and say ‘oh yeah, this thing is terrible’ or ‘this thing is great’, when, [actually,] it’s reasonable. There is the chance that, say we printed a really good two drop and somebody played that on turn two and then another copy of it on turn two, of course that would feel bad, and Innervate has that potential. But maybe one day we’ll put that in an expansion set and it’ll be a card that Druid has, and it’ll be around for two years, and people will use it if their deck supports playing multiple twos on two or something like that. And that’s an okay card to do. It wasn’t right for exactly what we wanted here, but it’s a reasonable design.Our objective a lot of the time when we make these changes, specifically with cards that aren’t really build-around at all, cards that just sort of go in any deck if they’re powerful enough, our objective with changing Innervate wasn’t to take it from an A+++ card to just an A+ card, because both of those, to my last point, still sort of fit in every deck, which is not what we want. Hopefully there is a space. Counterfeit Coin got used a lot in Rogue when Miracle was going on, and I think at some point there will be some meta where Innervate will be super useful for Druids when they need cheap spells for whatever the new Auctioneer is three years from now, or next year, when we decide to do something that makes having the new Innervate in your deck a really strong thing for you to do because it’s build-around.And [it’s] the same thing with Fiery War Axe. Our objective isn’t to make them A cards, to nerf them a little bit, because they just go in sort of every deck. We want them to be somewhat build-around. We want you to put Fiery War Axe in your deck when having weapons in your deck is a good idea because there are synergies in your deck, not just because – oh, this is an obviously great card that I’m going to put in my Control Warrior and my aggro Warrior and my any Warrior. So I think that getting them to a point where they’re good in specific situations is our goal, rather than making them still almost as good as they already are but just maybe not as powerful.Sure. We generally don’t want to have a lot of cards that you just put in any Druid deck or any Warrior deck, just as a general statement. Those are not cards that we’re super excited about making.For me personally, looking back on Spreading Plague, we have stuff in the game, like Eater of Secrets and Golakka Crawler, which I think are answers to – hey, I’m losing to Pirates, or I’m losing to Secrets, so I want an answer to go to in my collection that is good against those decks, but they’re not necessarily great to just put in all of your decks. I think Spreading Plague for me was – during playtesting – was really that. ‘I’m losing to swarm decks so I’m going to go out of my way to put in this card that’s not really good in most situations, and put it in my deck.’I think it’s more complicated than that. I think the total of Innervate plus this changes Druid’s win rate and it changes their tempo and how fast they can get set up, so I think it’s a combination of the two. It’s hard to tell how much the combination of these two cards will change it and if Druid just goes down a little bit and the other decks go up a little bit - so there’s a lot of classes very close together - hopefully that’s a good thing. Hopefully that means there’s a diverse meta. We didn’t want to make Druid too weak. We thought changes to two cards would probably be enough, but it was very close to [us] adding two mana to the card instead of one. We weren’t sure, it’s tough.We actually have other Druid cards that make 1/5 taunts – the two mana Druid of the Swarm and Malfurion [the Pestilent]. Both summon 1/5 taunts and they’re supposed to be the same minion – the Scarab, so lining those all up at 1/5 taunt makes sense to us.Also, I think that often when we’re designing cards, crazy things happening in Hearthstone is awesome. We love it when crazy things happen, but the craziest things we like to keep for the later turns of the game, and I think that summoning 30 health of taunts or 25 health of taunts is a crazy thing for you to do. I think later in the game for that kind of thing to be happening, in general, is a bit better. And it is a huge swing. You have these big 1/5 taunts – it’s hard for your opponent to get through. It’s a big wall. So I think that’s actually a pretty cool aspect of the card. Making them a lot smaller takes away from the cool aspect of the card, to make it more balanced, whereas increasing the mana cost doesn’t really take away from the cool aspect of the card, but still accomplishes the same goal.It’s so far away, I’m sure that what we want to change at that point will change in our heads twenty times, and what the fans ask for will change in their heads twenty times. But it’s certainly on our shortlist.Yeah, it’s something we talk about quite a bit, but I mean, we talk about it so frequently that it would be pretty crazy to confirm anything at this point, because I’m sure that list will change over time.(Laughs) Yeah, nothing should really be set in stone that far away. Things in Hearthstone change so frequently. The issues we have today aren’t going to be the same issues we have seven or eight months from now. Having anything confirmed that far ahead I think would be a bad idea.Be sure to check out the second half of this interview, in which we dig into the design of the Death Knight hero cards

Cam Shea is senior editor in IGN's Sydney office, plays a lot of CCGs and tries to spend as much time as possible in Japan. He's on Twitter