Battle.net Leagues

Note: Much of this article is based on empirical research and scattered Blue posts, so there might be errors and inaccuracies.

The Battle.net Leagues are SC2's replacement to SC1's ladders and are Blizzard's official player ranking system. There are currently seven Leagues, each divided into numerous divisions as well as a Practice League for rookies.

League Mechanics

The Leagues

	Grandmaster League
	Master League
	Diamond League
	Platinum League
	Gold League
	Silver League
	Bronze League

Ranked from the lowest to the highest, the Leagues are: Bronze, Silver, Gold, Platinum, Diamond, Master and Grandmaster. The Copper league, which was formerly below Bronze, was removed in favor of Diamond in beta patch 13. The Master League was added with patch 1.2, and the Grandmaster League was added in 1.3.

Players are placed in a league after having completed 5 placement matches. After that, a player may get moved to another league, depending on performance. Though the time and frequency of these movements are kept explicitly hidden. Regardless of a player's performance, however, placement matches currently do not place players in the highest league, Grandmaster. With even a perfect placement record, a player must work their way through the initial placement division(s) before being placed in Grandmaster.

It is currently believed that the top 2% of active players are in Master league and the remaining 18% of the top 20% of players are in Diamond League. The rest of the players are split equally between Bronze, Silver, Gold and Platinum.

Ratio of Players per League

League	Targeted Ratio of Active Players
Grandmaster	200 players
Master	2%
Diamond	18%
Platinum	20%
Gold	20%
Silver	20%
Bronze	20%

Divisions

There are numerous divisions within each League, with each division being composed of up to 100 players. While Leagues are grouped by alloy, divisions are grouped by number, such as Gold League/ Division 243. These divisions are exist to encourage the players, so that more people will be able to see their name among the top 10. Players are still regularly matched up against players from other divisions. Players ranked near the top or bottom of the ladder may also be matched up against players in higher or lower leagues, respectively.

Players do not move from one division to another within the same league. Though it is possible to end up in another division if a player is promoted or demoted out of a league and then demoted or promoted back into the same league later.

Divisions are not equal, and are instead separated into tiers containing specific offsets. Though the division tiers have a relationship with skill at the time of placement, lower tiers modify displayed rating by a particular offset that creates the illusion of remaining competitive with higher-tier divisions, thereby creating a normalized point range. Division tiers do not apply to Master and Grandmaster league.

Division Tiers (in Diamond league)

Division Tier	Rating Modifier
S-Rank	+0
A-Rank	+63
B-Rank	+126
C-Rank	+189
D-Rank	+252
E-Rank	+315
F-Rank	+378

Grandmaster League

Grandmaster league was added in patch 1.3 for 1v1 only. This league represents the Top 200 players in each region. Players are automatically drafted into the Grandmaster League shortly after a new season starts, and will remain in the Grandmaster League (unless removed for inactivity) until the end of the season. To enter the Grandmaster League:

• There needs to be an open slot within the ladder.
• A player need to be in the top 200 players according to a rolling average of their skill rating.
• A player's unused bonus pool must be less than 90.

If a Grandmaster player’s available bonus points gets higher than 180 due to inactivity, they will be automatically removed from the league and a replacement player will be drafted in. This means Grandmaster players can't get more than two weeks behind which is equivalent to roughly 30 games. (At an average of 12 bonus pool spent per win, 180 bonus pool would be spent after 15 wins, and at an expected 50% win rate, this works out to be 30 games)

Practice League

A Novice version of "Blistering Sands" is used in the Practice League.

The Practice League is separate from the rest of the ladder, which is a league that new players are able to play in to learn the game prior to their placement matches. It consists of up to 50 matches played on Novice versions of maps. The novice versions differ from the standard version as they also include destructible rocks which are placed in rushing paths to slow the game down. This provides early game protection for newer players, which affords them time to explore and learn both the interface and game.

After those 50 matches, regardless of whether a player wins or loses, they will progress to their placement matches for the competitive leagues. There is also an option to skip the Practice League.

You cannot initiate

• 3v3
• 4v4

in the Practice League. But you can play 2v2 with a friend, even if they are in a higher league. Moreover, you can join friends in 3v3 or 4v4 if one of those friends are not in Practice League and if he or she is the group leader. When you play with your out-of-Practice League friends, those games will count towards your limit towards 50 games in Practice League. Consequently, you can play all of your Practice League games with non-Practice League settings if you play them with a group leader who is out of Practice League.

"The other thing we're introducing is a casual league. It will work just like the regular league, except it doesn't do a bunch of ladder stats, so you don't have to worry about your rank and where you are. It'll be at a slower game speed setting, so it will be what you're used to from the campaign, and it will be on a bunch of maps that are anti-rush -- that are designed specifically to prevent rushing. Now, I can't promise you that you won't die at minute six -- you could be minding your own business and here comes a fleet of Banshees and, "Aaauugh! I'm dead!" -- but you won't die in minute two. I can promise you that. You'll at least have a chance to get your feet wet and experience some of the tech tree before you get rolled." (Quote by Dustin Browder - lead game designer)

Ladder is played on "Faster", game speed is set to "Normal" in Practice League. Like Dustin Browder says, these maps are "anti-rush", so 6 Pool is not effective on these maps.

Using the Practice League as a rookie is discussed controversial, regarding forum posts and other people's opinion. It is often suggested (in forums) to skip the Practice League, because rush and All-In strategies are part of the game. On the other hand getting better mechanics is a fundamental part of improving your skills. Solid mechanics and good macro will help you to climb the Ladder. As a rookie, you can concentrate on your mechanics more easily, if you play more slowly. And to develop solid mechanics is important to improve in SC2.

Points System

Players are ranked within their division based on their Points. Points only decide how a player is ranked within their division. After having completed their placement matches, players start out with 0 points.

Since there are no global or regional rankings, the displayed score isn't an accurate measure of skill when compared to anyone else. This is because the visible rating does not match the hidden MMR rating, and is influenced by the Bonus Pool. Each play-season the visible rating will be reset, while the MMR rating stays intact. This makes it even harder to derive the true skill of the player.

However, one fairly reliable method is to calculate adjusted points, or points without factoring in Bonus Pool. Subtract the total amount of Bonus Pool available so far in the season from a player's displayed points to find their adjusted points. The fewer the Bonus Pool remaining for a player, the more accurate their adjusted points are, and effectively the more accurate their skill level. A player with high points but negative adjusted points, for example, should not be surprised if he is demoted because a majority of his points originated from spent Bonus Pool.

Points and Promotion

On November 15, 2011, Blizzard released a chart for the current ladder season explaining the point cutoffs required to almost be guaranteed a promotion. This chart is a rough estimation of the number of points necessary to go from the bottom division tier of one league to the bottom tier of the next-highest league. The charts also contain information for 2v2, 3v3 etc., and for all regions.

Blizzard Chart (Points including Bonus Pool)
North America	1v1	2v2 Random	2v2 Arranged	3v3 Random	3v3 Arranged	4v4 Random	4v4 Arranged
Bronze to Silver	1200	1100	1000	1000	900	1000	900
Silver to Gold	800	800	700	700	700	700	700
Gold to Platinum	800	700	700	700	700	700	600
Platinum to Diamond	800	800	700	700	700	700	700
Diamond to Master	900	900	800	800	800	800	700
Master to near Grandmaster	1400

Blizzard Chart corrected for Adjusted Points
North America	1v1	2v2 Random	2v2 Arranged	3v3 Random	3v3 Arranged	4v4 Random	4v4 Arranged
Bronze to Silver	835	735	756	635	778	635	778
Silver to Gold	435	435	456	335	578	335	578
Gold to Platinum	435	335	456	335	578	335	478
Platinum to Diamond	435	435	456	335	578	335	578
Diamond to Master	535	535	556	435	678	435	578
Master to near Grandmaster	770

Earning and Losing Points

You earn or lose points by winning or losing matches, respectively. To simplify how it works in practice:

y = (+/-)12 + x + z

where

• "y" : the total number of points
• "x" : the relative expected skill level between one player's points and the other's MMR (can be negative, calculated independently per player)
• "z" : the points you get from your bonus pool

=> "x" is a value in the interval of [-12,12], positive numbers are when your opponent is favored

• if the game says you are even, "x" is part of {0,1,2}
• if it says your opponent is slightly favored, then "x" is part of {3,4,5,6,7}
• if it says your opponent is favored, then "x" is part of {8,9,10,11,12}

(of course, if you are the slightly/favored player, then "x" is negative, which means you will lose more or win less than 12 points)

"z" will be be greater than zero when

• your bonus pool is >0
• you are victorious

If these 2 conditions are met, then Z will be equal to 12+x, permitted you have enough points in your bonus pool.

Bonus Pool

The Bonus Pool is the sum of all "bonus points" a player can get, which are added to the rating points a player earns after a victory. The Bonus Pool serves two purposes: to encourage players to play games so their points are always trending upward, and as a global decay mechanism since all players have equal access to the same amount of Bonus Pool.

Players receive Bonus Pool points at a set rate per league. Before Season 3, all players received points at the Master league (original) rate. Season 3 introduced a separate accrual rate for leagues below Master. A player joining Starcraft freshly after the start of a season instantly receives the Bonus Pool as if he started at day 1 of the Season. (Example: Master League Player 1 joins on week 3 after the beginning of the Season he will receive a Bonus Pool of (90*3) 270 Points instantly after finishing his Placement Match.)

Bonus Pool Accrual Rate

League	Time per 1 Bonus Pool	Bonus Pool per Week
Grandmaster	112 minutes	90
Master	112 minutes	90
Diamond	193 minutes, 6 seconds	52.2
Platinum	193 minutes, 6 seconds	52.2
Gold	193 minutes, 6 seconds	52.2
Silver	193 minutes, 6 seconds	52.2
Bronze	193 minutes, 6 seconds	52.2

Arranged 2v2 teams receive Bonus Pool at 66% the rate of 1v1. Arranged 3v3 and 4v4 teams receive Bonus Pool at 33% the 1v1 rate. This change was made in Patch 1.3 to make it easier to spend Bonus Pool on arranged teams, because of the logistics of having to play with the same teammates every time. Random 2v2/3v3/4v4 uses the standard 1v1 Bonus Pool accrual rate because those game modes can be played whenever the individual player decides to queue.

Effects of Promotion or Demotion

After a player is promoted or demoted into a different league, points are always reset to 73 + spent bonus pool. Because of this, bonus points earned are never lost when changing leagues.

Hidden "Matchmaking Rating" (MMR)

In addition to points, there is also a hidden Matchmaking Rating, presumed to be very much like the WoW Arena Matchmaking System. This rating decides which opponents a player will meet, and tries to quantify their skill level. The aim of the MMR is to rank players in such a way that they have a roughly 50% win ratio when paired against those of similar MMR. Players presumably start out with an MMR of the middle of the spectrum when starting their placement matches. When a player's MMR has averaged above or below a certain value over a number of recent games, they can be promoted or demoted.

There also is a value "sigma" (i.e. standard deviation) that measures how uncertain the system is of a player's MMR. This is usually high if a player has not played many games recently, or if they are on a winning or losing streak. The system does not seem to use sigma for purposes other than to calculate how much it should adjust a player's MMR after a win or loss (i.e. for Bayesian inference). For example, it uses a moving average of MMR to promote and demote between leagues, instead of MMR and sigma to calculate the probabilities that some league is most appropriate.

MMR persists from one season to the next for each game type as long as a Seasonal Placement Match was played for that season. If a Seasonal Placement Match was not played last season, then MMR and uncertainty are both reset to their default values and the system effectively "forgets" about that player. A special note about this, though: Random Team MMR is linked with 1v1 MMR, which means that if no 1v1 games were played last season, but Random Team games were played, a player's 1v1 MMR would not be reset at the start of the next season.

2v2 Mechanics

Every pair of players is ranked individually. So players A+B's team will have a ranking completely unrelated to players A+C's team. In 2v2 random match-ups, an average rating of the two players will be compared to their opponents rating. This rule presumably applies for 3v3 and 4v4 as well.

Seasons and Winners

During the beta, there were regular resets of the ladder; such a reset could be regarded as the end of a season. Though before the resets, the rankings were never published. For Season 1, Blizzard had been publishing weekly listings of the top 200 players in each server, but for the last week of the season no such listing was published.

From Season 2 and onward, the Grandmaster League had been implemented, so the final rankings of the Grandmaster League should be considered the winners of the season.

Retail seasons:

• Season Seven: 11 April 2012 - TBA
• Season Six: 14 February 2012 - 11 April 2012 (Season six lock begins on 4 April 2012) Rankings: Battle.net Leagues/Season 6 GM Rankings
• Season Five: 20 December 2011 - 14 February 2012 (Season five lock begins on 7 February 2012) Rankings: Battle.net Leagues/Season 5 GM Rankings
• Season Four: 25 October 2011 - 20 December 2011 (Season four lock began on 12 December 2011) Rankings: Battle.net Leagues/Season 4 GM Rankings
• Season Three: 26 July 2011 - 24 October 2011 (Season three lock began on 10 October 2011) Rankings: Battle.net Leagues/Season 3 GM Rankings
• Season Two: 29 March 2011 - 26 July 2011 (Season two lock began on 5 July 2011). Rankings: Battle.net Leagues/Season 2 GM Rankings
• Season One: 27 July 2010 - 29 March 2011 (Season one lock began on 29 March 2011) (Second-to-last week of top 200 listings: NA EU, SEA, KR, )

Beta ladder "seasons":

• 7 July - 19 July (from start of phase 2 of beta to the end of beta)
• 4 June 2010 - 7 June 2010 (from fourth wipe to the end of phase 1 of the beta, coinciding with beta patch #16, Patch 0.18.0)
• 22 May 2010 - 4 June 2010 (from third wipe to fourth wipe, coinciding with beta patch #15, Patch 0.17.0)
• 24 April 2010 - 22 May 2010 (from second to third wipe, coinciding with beta patch #13, Patch 0.15.0)
• 25 March 2010 - 24 April 2010 (from first to second wipe, coinciding with beta patch #10, Patch 0.12.0)
• 17 February 2010 - 25 March 2010 (from start of beta to first wipe, coinciding with beta patch #6, Patch 0.8.0)

See also

• 2012 Battle.net World Championship