Tian Ding

Greetings, everyone! I’m Tian, a Senior Data Scientist on the Hearthstone team, and I’m here to talk about the new smart deck builder feature. I’m hoping to answer some of the questions that have bubbled up in the community since this feature was recently introduced.

Let’s start off with a simple introduction to the feature before we dive into what I know you’re really here for – the science!

What is the Smart Deck Builder?

We know that creating a new Hearthstone deck can be a fun and rewarding experience for a lot of experienced players, but maybe you’ve taken a break from Hearthstone, or you’re new to the game, or you’re on a time crunch, or just need a little help turning your collection of cards into something you’re proud to take to the ladder. That’s where the smart deck builder comes in. Its purp...

Hi! I’m Tian, a Senior Data Scientist with the Hearthstone team, and today we’re talking about the math behind Arena balance.

Arena matches are played all the time, and they constantly generate data—A LOT of data—that we can use to help make sure that Arena is more balanced. If you had to place me in Boom Labs, I’d probably be in the Mathematical Science department!

The Balancing Game

Arena balance is done in two stages. First, we determine which bucket(s) each card goes into (a bucket is a subset of cards with similar performance quality). A card generally falls into two buckets, and we divide Legendary and non-Legendary cards into two different bucket systems. We decide which bucket each card falls into by its win-rate and pick-rate during games. That means each of the three cards you see during a pick are on similar power tiers.