Battlegrounds will see some major changes with the upcoming patch, as in addition to the already-announced rating reset, Elementals will join the fray as a new tribe!

Rating Update

Here are the new features of the rating system coming in Patch 18.4. in a nutshell:

  • All external ratings will be reset to 0, which will serve as the new baseline.
    • The reset will happen every season.
  • Rating floors will be introduced.
    • You cannot lose rating below 2000.
    • Between 2000 and 6000, there will be rating floors after every 500.
    • Below 6500 a small rating bonus will be awarded after every match.

You can read the complete patch notes and the dev insights blog about the system within the spoiler below.

Rating Update Notes

Quote From Blizzard

Battlegrounds Ratings Update

External Battlegrounds ratings will be reset for all players and a new progression system will be introduced. The new system is similar to the progression system players are familiar with from our constructed Ranked mode.

Players will see their rating reset to 0, and all new players will start with 0 rating. With every Top 4 placement, players will gain rating—up to 300 per win. A player's rating will never go below 0, and they cannot lose rating until they’ve climbed above 2000.

Here are the nuts and bolts of how the new system works:

  • Between 2000 and 6000 rating, every 500 rating (2500, 3000, etc.) will act as a new rating floor where you cannot lose rating.
  • Below 6500 rating, players will earn a small bonus to their rating gains at the end of each match, which will in turn make for a faster climb.
  • Rating losses will remain consistent.

Matchmaking will now be done based on the player's invisible internal rating, which we’ve been tracking since Battlegrounds launched. Internal ratings for players will not be reset and will not be affected by the above modifications to external ratings. When your external rating is lower than your internal rating, you will gain rating faster. Read more about the ratings update in our Dev Insights blog! 

Please note that your rating will not visibly reset until you've played at least one Battlegrounds game!

Quote From Blizzard

Greetings! I’m Tian, a Lead Data Scientist on the Hearthstone team. In 18.4, we are updating our Battlegrounds rating system and I’m here to talk about some science behind it!

Before I get into it, check out our previous blog on Battlegrounds rating if you’re interested in understanding the basics about personal rating and what it represents, how it’s updated after each game, and how variance works.

Now, let’s go to the main topic—the new rating system!

What are the motivations behind updating the rating system?

We want our rating system to both provide a sense of progression through gameplay and create fair matchmaking. It’s very hard to achieve these two things simultaneously by using only one rating. Therefore, we designed a “dual-rating” system to address our intention. In the updated rating system, there are two ratings—external rating and internal rating:

  1. External rating: this rating is shown in your Battlegrounds lobby interface. The main purpose of this rating is to provide seasonal “progression”, as well as partially or fully reflect your actual skill.
  2. Internal rating: this rating is invisible to you. The main purpose of this rating is to help us estimate your actual skill at all times and thus create fair matchmaking.

What are the updates on the external rating (player facing)?

  1. Your external rating is reset to 0 at the start of each season (18.4 is the start of the first season).
  2. There is a rating “protection zone” at the start of the season—you are not able drop external rating if it is below or equal to 2000. Therefore, rating 0 is the minimum possible rating you would see on your user interface.
  3. There are rating “floors” between 2000 to 6000 for external rating. Your external rating does not drop below each “floor” once it’s above it. Currently there is a floor every 500 rating: 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000.
  4. Your maximum external rating gain per match is 300.
  5. After each game, if your external rating is below 6500, we will give you a very small value of positive rating gain, on top of your “actual” rating change, which could be either positive or negative. For example, in theory your rating would be added/subtracted by 50 after a game, but since we give you 3 progression points, in reality your rating value will be added/subtracted by 53/47. That small value is determined solely by your external rating—the smaller your external rating is, the bigger this “progression value” would be. Note that this number is so small that you won’t even feel it unless you play many games. When your external rating is above 6500, this value is set to 0.

What are the updates on the internal rating (under the hood)?

Your internal rating, which is invisible to you, will never get a seasonal reset like the external one.

The overall distribution of the internal rating should follow a bell-shaped curve – in mathematics terms, “normal distribution”. We might enforce this distribution by performing a procedure called “re-normalization” to your internal rating from time to time. Such adjustments are usually very small but necessary!

The internal rating is not limited to any rating protection zones or rating floors like the external one, and there are no progression factors being added on top of that. You and your opponents’ internal rating and variance are updated completely based on your game result.

How is matchmaking affected?

We will match players based on their internal rating only, as it is designed to always truly represent your actual skill. During the match building phase, we will try to select eight players with the closest internal rating to ensure the match is as fair as possible for everyone.

Meanwhile, external rating plays no role in the matchmaking process. Therefore, it is possible a player with 7000 external rating is in the same game as a player with 1000 external rating, if their internal rating values are close. If you see a player with 0 rating in a high level Battlegrounds game, it’s because they have a high internal rating and are likely just getting started with the Battlegrounds season!

How do external rating and internal rating interact with each other?

As everyone starts the season with 0 external rating, and matches are “fair” in terms of skill, generally we want players with higher internal ratings to receive more rating gain after each win, while keeping the amount of rating lost after each loss the same for everyone.

Specifically, when your pre-calculated rating gain is positive, it would be multiplied a factor called a “rate gain modifier”. This modifier is proportional to the discrepancy of your internal rating and external rating, when your internal rating is larger than your external rating. You can think of this as a “chasing” process, as the external rating is “chasing” the internal rating. If your external rating exceeds your internal rating, the chase stops.

We hope you enjoy Hearthstone Battlegrounds! We are constantly listening to your feedback - feel free to share any matchmaking and rating comments with us. We’ll see you all in the Tavern!

New Tribe: Elementals

Get ready for a true upheaval as the elements themselves are rumbling into the Battlegrounds. A total of 16 new Elemental-synergizing minions will be added when the patch goes live.

Four New Elemental Heroes

What would a new tribe be without some thematically appropriate heroes to go alongside it! The heroes will be formally released on October 13 but Tavern Pass owners will get their hands on them right from the beginning of the patch.

The price of the Tavern Pass will be reduced for the reminder of the expansion cycle today so take advantage of it!

Ragnaros the Firelord

  • DIE, INSECTS! [Passive]
    • After you kill 20 enemy minions, get Sulfuras.
  • Sulfuras [Passive]
    • At the end of your turn, give your left and right-most minions +4/+4.

Chenvaala

  • Avalanche [Passive]
    • After you play 3 Elementals, reduce the cost of upgrading Bob's Tavern by (2).

Rakanishu

  • Tavern Lighting [Cost 2]
    • Give a random friendly minion stats equal to your Tavern Tier.

Al'Akir the Windlord

  • Swatting Insects [Passive]
    • Start of Combat: Give your left-most minion Windfury, Divine Shield, and Taunt.

Bug Fix

It's not a proper patch without some minor fixes as well.

  • Fixed a Battlegrounds bug where Micro Mummy would cause a crash when tripled. Micro Mummy has returned to the Battlegrounds minion pool.