The next Hearthstone patch resets Battlegrounds ratings and nerfs two problem cards

Hearthstone next patch has just been announced by Blizzard, and it's a juicy one. Known as version 18.4 to its friends, the update brings the start of the Masquerade Ball limited-time event, the return of Dual-Class Arena, and a new Hearthstone Book of Heroes featuring Rexxar. It also adds elementals as a new Battlegrounds minion type while simultaneously resetting everyone's Battlegrounds rank (more on that in a moment), and delivers a couple of balance updates aimed at Standard. Phew. Let's get into it.

The nerfs being made are to Guardian Animals and Tortollan Pilgrim. The latter was essential to Turtle Mage, one of the most annoying Hearthstone decks of all time.

As of 18.4, Tortollan Pilgrim's Battlecry will no longer Discover and play a copy of spell from your deck, instead it will consume the spell you pick. This should prevent the use of Tortollan Pilgrim to draw a copy of Potion of Illusion so you can use it to copy Tortollan Pilgrim and set up the tedious loop that was Turtle Mage's whole thing. That change should effectively kill the deck's win condition, although better brains than ours might find a way to salvage it somehow.

The other nerf is to Guardian Animals, a 7-mana Druid spell that summoned two Beasts that cost five Mana or lower then gave them Rush, which has been particularly obnoxious when used in combination with Lake Thresher, Twilight Runner, and Teacher's Pet. Thanks to Druid's glut of ramp cards like Wild Growth, Innervate, Overgrowth, and Breath of Dreams, hitting seven Mana is a piece of cake. 

Blizzard presumably either had a choice between changing multiple ramp cards or hitting Guardian Animals, and opted for the simpler option. Whether a single point of Mana will be enough to defang the deck remains to be seen, but small cost changes can often have a major effect because they push power spikes back by a whole turn.

Both Guardian Animals and Tortollan Pilgrim will be eligible for full dust refunds for two weeks after the patch goes live.

⚠️ Battlegrounds Rating Reset Incoming ⚠️Prepare for a fresh field! Next week, all players' Battlegrounds rating will reset to 0 to make way for a new rating system. More details coming soon! ???? pic.twitter.com/4E1teTuwgcSeptember 24, 2020

As for the reset of Battlegrounds ratings, a data scientist from the Hearthstone team named Tian has shared some of the details of this update and the reasoning behind it in a developer insight blog. The main change will be that every player receives two ratings: An external one they can see, and an internal one they cannot. 

The invisible internal rating will exist solely for the purpose of matchmaking, and be based purely on game results. As Tian explains, "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."

While essential in matching players of equal skill, the internal rating would be a disappointing thing to see. Since it's graded on a curve the average player keeping up with the game, getting steadily better at the same rate as everyone else, would stay smack-bang in the middle. To encourage improvement, you need a way of comparing your skill today to your skill yesterday, and that's what the external rating system is for.

"The main purpose of this rating is to provide seasonal 'progression', as well as partially or fully reflect your actual skill", Tian writes. The external rating will be right there in the lobby interface, and while everyone's being reset to zero with this week's 18.4 update, and then again at the start of each subsequent season, the rating will adjust quickly to make up discrepancies. If you've got a high internal rating, your external rating will tick up faster with gains multiplied by a modifier. "This modifier is proportional to the discrepancy of your internal rating and external rating," Tian writes, "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."

The maximum external rating gain per match is 300, and everyone with a score below 6,500 gets "a very small value of positive rating gain" per match, regardless of result, as an incentive.

Meanwhile, a protection zone at the start of each season will prevent the external rating from dropping below zero and "floors" at every 500 points between 2,000 and 6,000 will stop you from falling below them because of a few poor matches. It'll take some of the dispiriting sting out of losing to know that at least the number you can see remains a permanent indicator of your past success. 

Psychologically speaking, it's always healthier to compare yourself to yourself in the past, and it's better motivation for improving your actual skills. When it comes to fictional heroes you should definitely compare them to each other though, and here's our tier list of which Battlegrounds Heroes to pick and to avoid. Just don't let Professor Putricide see it.

The dual class arena and elementals will go live on September 29, and Rexxar will follow on October 13. Details are up at playhearthstone.com.