Power Creep in Hearthstone - What It Teaches Us About Games - Extra Credits

Long ago, we did an episode on power creep. We covered what it is and the damage that it can do to a game in the long term. We wrapped it up with a nice bow and bam, work complete. Or so we thought. Then the new Hearthstone expansion came out and as we were reading through the boards, we saw a lot of people complaining about power creep, but a surprising number of them were pointing to the wrong examples, to cards that weren't actually causing power creep. And it occurred to us that in that whole first episode on power creep, we never really explained how power creep happens from a design perspective. This seems like a fantastic time to fix that oversight. Now, of course, sometimes power creep is conscious. Sometimes it's an attempt by the developer to sell whatever expansion they just released by making the gear or the cards in it so much better than what they'd released previously that anybody who wants to stay competitive has to buy it. But this sort of intentional power inflation is usually pretty obvious to everybody and the self-destructive long-term cycle there is pretty clear. So, that's not what I want to talk about

today. Instead, I want to talk about the more interesting type of power creep, the accidental kind of power creep that inevitably happens as designers work on increasingly complex sets of interlocking pieces, like cards in a collectible card game or equipment in an MMO. We're going to use Hearthstone as an example here, but you won't have to know the rules of Hearthstone to follow this episode. Although, if you do want to do a quick brush up on the rules before watching, it won't take you very long. If you do like collectible card design, you'll probably dig this. The only piece of terminology we all have to be clear on before moving forward is power curve. The power curve of a card game refers to the curve created by plotting the power and cost of each card on a graph. While there will be some variation, all of the game's cards should basically fall along that curve. If a card spikes too high over that curve, it risks breaking your game. If it spikes too low, it risks being too weak to be worth any player's time. Make sense? Okay, here we go. In the The expansion to Hearthstone, Blizzard released two particular cards that have frequently been cited as examples of

blatant power creep, Evil Heckler and Ice Rager. This is because Evil Heckler is a strictly better version of a previously existing card called Booty Bay Bodyguard. Notice how Evil Heckler has the same stats as Booty Bay Bodyguard, but costs one less mana to play. It is an objectively better card in any scenario. And look at Ice Rager, it is a strictly better version of an existing card called Magma Rager. See how it has one additional hit point? There is no reason to ever choose Magma Rager over Ice Rager when building a deck. Now it's easy to see why one might look at this and at first glance mistake it for a textbook case of power creep, but it's actually not at all. Why not? Because Magma Rager and Booty Bay Bodyguard were actually themselves so far below the power curve that they were already completely unplayable. All the designers did here was take cards that are unplayable in any format and made new versions of those cards that might in some scenario at some time possibly have a chance of seeing play. So while these new cards are indeed more powerful

than the existing ones, both of the new cards still fall below the game's overall power curve. It's only power creep when a card or a piece of gear spikes above the game's power curve. And because for most decks there are already better cards in the three to four mana range, these new cards don't actually push the power level of the set or force players to go buy them to stay competitive. They're not competitive right now and nothing about them suggests that any cards made in the future are going to synergize with them in a way that makes them substantially stronger than other cards that already exist. So yes, they are clearly better than certain other cards that already existed, but they in no way impact the overall power level of the game. So these sorts of correction cards aren't what we're looking for when we're hunting for power creep. Instead, we're looking for things that are so far above the curve that all future cards of that mana cost must be compared against that card. One such card in the previous set was Piloted Shredder. Ever since its release, players looking to put any four-cost minion in their deck have had to ask themselves, "Is this card somehow better for my deck than Piloted Shredder

to justify putting it in?" This means that any future four-cost minions worth playing are going to have to be better than Shredder to see play. And Piloted Shredder was itself already better than all the previous four-cost minions. This is the definition of power creep. Now, of course, there are cases where some specific combination of cards makes another four-cost minion better for a specific deck than Piloted Shredder. But even in those cases, that question is always how the player makes that call. They simply ask themselves, "Would I rather have a Piloted Shredder in here?" And you can see the immediate impact it had on the next Hearthstone expansion, too. Notice how there are a lot more three-strength, five-health minions in the next set, specifically because those minions can kill the Shredder without dying to it, allowing them to stay on the board and have a chance at also destroying the minion the Shredder will spawn when it dies, which shows you just how much that accidental power creep impacted the entire set and how the folks at Blizzard had to try to use the tools they had available to haul the Shredder's power back into line with this new expansion. And here's where the

mechanics of power creep come into play. If Blizzard can't haul the power of that card back down by releasing a bunch of cards specifically designed to counter it, then in the future, their only option is to release cards on par with or better than the Shredder in that four-mana slot, at least if they want those cards to ever have a chance of seeing play. But because the power of the Piloted Shredder is already so high, if they release cards superior to it for the four-mana slot, those cards will likely be as powerful as existing cards in the five-mana slot, which means that Blizzard's going to have to make more powerful five-mana cards to give players a reason to bother with five-mana minions at all. And if they release more powerful five-mana minions, well, then this effect just cascades, and they have to release more powerful six-mana minions, and on and on until they've eventually released more powerful minions in every slot. Once they do, the power curve will finally look right again, exactly like it did before any of this happened, except now it has a new baseline. And that is how power creep works. So, if you're a designer and you're looking to avoid power creep, you

don't have to worry about correcting past mistakes or making more playable versions of existing underpowered cards. No, what you've got to worry about is letting cards accidentally slip by that form the new baseline for how players judge cards at a given point in your power curve. Because once you let those through, they've basically deleted all the design space below them. All those decent to mediocre cards that might have been playable in certain interesting edge cases will no longer be worth bothering with because they've simply been outclassed. And that's a dangerous thing if you want your game to last 10 years. Which actually leads us nicely into a new topic. How do you avoid this kind of long-term damage? Is it possible to future-proof your design? We will talk more about that next week. See you then.