Since we introduced a new ladder with the launch of Heart of the Swarm, we’ve been continuously reviewing your feedback about league placement and the matchmaker in StarCraft II. In particular, recently we’ve seen some discussion in the community about the current state of the ladder. We wanted to take this opportunity to address those discussions, clarify some misconceptions, and mention some changes we plan to make.

Right before we launched Heart of the Swarm, we announced that we were changing our targets for player distribution across leagues. For various reasons since that announcement, the distribution of players across leagues slowly shifted to no longer match those desired targets. Currently the lower leagues like bronze and silver have a larger percentage of players than desired. Meanwhile the upper leagues like platinum and diamond are under-represented. One of the reasons this occurred is due to the way that we maintain those target percentages.

Accordingly, around the time we release the 2.1 patch, we are changing how league boundaries are determined so that we can more closely match the desired percentage of players in each league. Thereafter, we expect to see a shift in the distribution of players across the leagues to their correct placement within the ladder. Because of the current bottom heavy distribution, many players may see a league promotion as a result of this change.

Recently there has also been some community discussion over what some players are calling “MMR decay”. This is the slight adjustment to a player’s hidden rating that occurs after that player has been inactive for a period of time. We implemented this automatic adjustment with Heart of the Swarm, after we found that players who returned to the ladder after a period of inactivity were frequently suffering a string of consecutive losses. That experience can be demotivating and discouraging.

Since there is some confusion in the community, we want to make sure that the way this adjustment works is fully understood. Specifically:

• Each ladder queue is adjusted separately. For example, an absence from games in team queues will not adjust your 1v1 matchmaking rating.
• The adjustment only kicks in after a player has played no games (ranked or unranked) in a given queue for more than two weeks.
• Once it kicks in, the adjustment ramps from zero adjustment to our maximum adjustment over a period of two weeks. There is no further adjustment after four weeks of inactivity.
• At its maximum value, the adjustment is small; it’s the equivalent of losing a few games.
• If a player plays even a single game on the ladder every two weeks, their hidden rating will never be adjusted downward.

Prior to implementing this feature, data gathered from games played on Battle.net showed that even an absence of only 7 to 14 days results in a drop of a player’s win percentage. The drop becomes more pronounced as the length of time away increases. After we introduced this change, the data showed that we see a win percentage for returning players that’s right around 50%. This is especially important for the first few games played after a player returns. Additionally, to address the misconception that the majority of players are being adjusted in this way, the data shows that less than 6% of all StarCraft II games played on Battle.net are affected by this adjustment.

While we have evidence that the adjustment is helping players, we’ve also been reading your feedback and analyzing the way the system is working. As a result we are currently looking at the following areas:

• We’re looking into possible changes to the way adjustments are made in team games.
• We’re considering altering the time period before the adjustment kicks in.
• We’re also considering altering the amount of the adjustment.

We continue to investigate ways to improve the experience of climbing the ladder. We want players to know when they’re moving up, and for those who want more granular details, better indications of how they’re doing competitively. We’re exploring ways to let you know when you are getting close to a promotion.

Finally, our balance team continues to monitor play results at all levels as they make their fine-tuning decisions. We've received a lot of good feedback from the community on that subject, and look forward to evaluating that aspect of the game separately after the release of patch 2.1.

We greatly appreciate your feedback and encourage you to share your thoughts in the comments below.