You may also be looking for Summoner Mastery, a retired feature of the game.
Champion Mastery 1

Champion Mastery is a progression system which tracks a player's aptitude and experience with each champion. At the end of every game, players receive a grade which scores their performance in comparison to the whole player base in that respective champion and position combination. These grades then translate into a point score which accumulates over time, eventually unlocking new Champion Mastery levels and rewards as the player advances through the system.

While implemented with patch V5.6, this system wasn't fully implemented on all servers until patch V5.8.

Riot's official support page on Champion Mastery can be found here.

How the System Works

Eligibility

At summoner level 5 and higher, summoners are eligible for Mastery points. Champion Mastery points are eligible on matchmade games of:

All Co-op vs. AI modes and custom games are not eligible for Champion Mastery.

Grades

Champion Mastery 2

Grading score

Every eligible game you play with a champion, you will earn a grade based on how well you performed in comparison to all other players in your region that have played your champion-position combination (e.g. Vel'KozSquare Vel'Koz bottom lane will only be compared to other Vel'KozSquare Vel'Koz bottom lane players), with S+ only being awarded to the highest percentile of players.[1]

These grades only represent how well you performed in that specific game. However, a higher grade is worth more points towards your mastery of that particular champion.

The possible grades you can achieve are (from highest to lowest): S+, S, S-, A+, A, A-, B+, B, B-, C+, C, C-, D+, D, D-.

Notes
  • While you are graded versus all players in your region, the grading system is not influenced by your matchmaking rating (MMR). Note that it is still possible for low-elo players to consistently get S+ if they are really good on a champion.[2]
  • Performance uses a mix of core game metrics that Riot is confident cannot be abused through means such as AFK farming or spam warding.[3]
  • Riot will not reveal the exact factors that determine grading to prevent players from attempting to game the system.[4]

Champion Points

Champion Mastery 3

Grading system

Champion Mastery is currently divided into 7 levels, with level 7 being the highest. To progress through the levels, a player needs to play games on your champion and earn champion points (CP). The amount of mastery points earned is displayed as a circular progress bar around your grade in the post-game screen. While a higher grade is worth more mastery points, the amount of mastery points gained is also influenced by team performance and party size (premade bonus).

$ \pagecolor{Black}\color{White}{\rm Champion \ Mastery \ Gain} = {\rm Individual \ Contribution} + {\rm Team \ Performance} + {\rm Premade \ Bonus} $

Team performance is affected by whether or not your team wins.

Premade bonus is awarded based on group size:[5]

Premade Size Premade Bonus
Party of one No bonus
Party of two 2% of CP earned
Party of three 4% of CP earned
Party of four 6% of CP earned
Party of five 10% of CP earned

Players can track their progress with each champion outside the post-game screen in the Champion section of their profile. Furthermore, the three champions with the highest point score are displayed prominently on the profile landing page, next to your ranked standings.

Levels 1 to 5

Unplayed champions are considered level 0. After playing a single game, players immediately enter level 1 and start their progress towards level 2.

Mastery points can be earned beyond level 5. The total is displayed below the champion portrait on the profile screen together with the level 5-7 crest.

The following describes the amount of Champion Mastery points required to go from one level to the next:

Level CP Required Cumulative CP Required Cumulative CP %
Champion Mastery Level 1 Flair 1 0 0 0
Champion Mastery Level 2 Flair 2 1800 1800 8
Champion Mastery Level 3 Flair 3 4200 6000 28
Champion Mastery Level 4 Flair 4 6600 12600 58
Champion Mastery Level 5 Flair 5 9000 21600100

Levels 6 and 7

Hextech Crafting champion mastery

Champion mastery tokens in Hextech Crafting

Upon reaching level 5, as noted above, champion points can still be earned but will not continue to advance mastery level. Instead, levels 6 and 7 are earned through Hextech Crafting.[6]

Gaining tokens

At level 5 with a champion, that champion becomes eligible to earn Mastery tokens. These tokens can only be earned on matchmade Summoner's Rift icon Summoner's Rift normal and ranked games.

  • At level 5, receiving a grade of S-, S or S+ grants one Mastery 6 Token.
  • At level 6, receiving a grade of S or S+ grants one Mastery 7 Token.

Using the tokens

Leveling up a champion's mastery requires combining the following:

Level Cost
Champion Mastery Level 6 Flair 6 Two Mastery 6 tokens + BE icon 2450
Champion Mastery Level 7 Flair 7 Three Mastery 7 tokens + BE icon 2950

In both instances, the BE icon blue essence can be replaced with a champion shard or champion permanent of that champion.

Note that you cannot gain more tokens once you have 2 tokens for Mastery 6, and 3 tokens for Mastery 7.

Rewards

There are 7 levels of Champion Mastery currently obtainable. You will earn the crests below as you accumulate Champion Mastery points. In additions, levels 4 and up get access to a Mastery badge emote for the loading screen (profile badge) and an in-game announcement banner, as well as Emote (bound to its seperate hotkey).[7]

Champion Mastery 4

Champion Mastery displayed beneath champion icons

Champion Mastery Kill Announcement

Announcement Banner (Shown: Level 7 Morgana kills a Level 7 Morgana)

Titles

At each rank, there is also a role-specific title which can be seen on your profile. Below are the titles at each rank for a given role.

Level Assassin Fighter Mage Marksman Support Tank
Champion Mastery Level 1 Flair 1 Rogue Scrapper Initiate Tracker Aide Grunt
Champion Mastery Level 2 Flair 2 Prowler Brawler Conjurer Strider Protector Bruiser
Champion Mastery Level 3 Flair 3 Cutthroat Warrior Invoker Scout Keeper Bulwark
Champion Mastery Level 4 Flair 4 Reaper Veteran Magus Ranger Defender Enforcer
Champion Mastery Level 5 Flair 5 Slayer Destroyer Warlock Pathfinder Guardian Brute
Champion Mastery Level 6 Flair 6 Executioner Warmonger Sorcerer Sharpshooter Sentinel Colossus
Champion Mastery Level 7 Flair 7 Deathmaster Warlord Archmage Sniper Warden Juggernaut

Notes

  • Free to play champions can be leveled up to level 4. After that, they will stop accruing points until the champion is unlocked.[8]
  • Mastery points do not decay.[9]
  • Progress will not be reset in the event of a champion rework.[10]
  • Visibility of Champion Mastery to other players:
    • Profile Page:[11]
      • Top three champions (by level, then by points)
      • Mastery Score: Sum of all Mastery levels attained
    • Loading screen and in-game rewards as detailed above
  • When changing server regions, the highest grade earned on that champion will be cleared, however the mastery rank obtained pre-migration will be kept. 

FAQ

Taken from the introduction page. Outdated information is noted in italics.

Details:

Will I get xp credit for how much I've already played a champion?
We’re not currently planning to do this. Because this is a new system, we want players to feel progress (and earn rewards!) based on how well they do and the champions they choose to play.

What goes into the grading system? How do you calculate it?
It’s based on the champion and role that you just played in a game. So, for example, we look at Annie mid differently to Annie support. We take a series of performance metrics and compare how you do to all other players in your region in your champion / position combination. It is percentile driven - so earning a high score means you performed in the top x% of players on that champ in that position. The grade itself governs the point gains.

How many games will it take to level up?
We expect players to take 15-30 games to level through the first set of levels (1 through 5). We’ll be unlocking additional levels later.
Levels 6 and 7 now available

Is this going to feel grind-y?
This system is performance based - the quicker you master a new champion, the quicker you’ll make progress.

At the same time, we want it to be accessible enough that all players can feel good about improving.

We’re tuning this system so that you will be leveling up the set of champions that you really enjoy playing and getting meaningful feedback on your performance each game. The ceilings are intentionally set low for each individual champion to avoid making it feel like a grind.

Can you be demoted?
No demotions or decay is currently planned.

What other kinds of rewards are planned for the future?
We are going to see how people enjoy using the system and what they like about it before we finalize our future plans. We’d love feedback on this.

Will skins ever be a reward?
It’s not something we’re considering right now, but we are exploring other ideas for unique rewards we think you guys might like.

Will this work on Dominion and ARAM? Will it ever in the future?
We’re currently limiting this to SR.
Now available on all player vs. players modes on all maps. Co-op vs. AI and custom games still do not reward champion points.

Can the enemy team see the crests in-game or in the loading screen?
Not initially, but we may revisit this in the future.

Can other players see my grade at the end of the game?
No. These grades are for you and not something for others to be able to see. They will not available to 3rd party sites either.
Grades of S- and above are announced to the allied team.

Will the score account for AFKers?
Can confirm, AFKing will result in a bad score."

Champion Mastery Loading Screen


Media

LoL Animations - Champions mastery

LoL Animations - Champions mastery

Patch History

V8.11
  • On Howling Abyss, champion mastery scores are now more easily gained. The performance required to get an S will be more consistent with Summoner's Rift.
V8.5
  • Blue Essence cost to upgrade a champion's mastery level to 6 reduced to BE icon 2450 from BE icon 3250.
  • Blue Essence cost to upgrade a champion's mastery level to 7 reduced to BE icon 2950 from BE icon 3900.
V7.15
  • Bug Fix: Champ Mastery level up notifications no longer pop over the Honor vote.
V7.7
  • Champion Mastery can be earned in All Random Summoner's Rift.
V6.12
  • Champion Mastery can be earned in matchmade ARAM and Twisted Treeline games, though not for Champion Mastery 6 and 7.
  • Champion Mastery can be gained with special game modes such as Ascension, Legend of the Poro King, Ultra Rapid Fire, Hexakill, and One for All. All Co-op vs. AI modes and custom games still do not allow players to earn Mastery points.
V6.10
  • New mastery badge emotes, loading screen border flags, and announcement banner upgrades for each level.
  • New Mastery 6 tokens, gained with S-, S, and S+ games with champs that are Mastery Level 5.
  • New Mastery 7 tokens, gained with S and S+ games with champs that are Mastery Level 6.
  • Combine Mastery tokens for a specific champ with that champ's crafting shard, permanent loot, or blue essence to unlock their next mastery level.
    • Mastery 6: 2 tokens and (BE icon 3250 or the champion's shard or champion's permanent shard).
    • Mastery 7: 3 tokens and (BE icon 3900 or the champion's shard or champion's permanent shard).
V5.15
  • Tier-4 and Tier-5 animation is now visible to enemies (previously announced tier-5, but it should now be working now).
  • The in-game mute now suppresses the champion mastery emote (both allies and enemies).
V5.11
  • At rank 5+, the Mastery Emote is visible to the enemy team.
V5.8 - May 6, 2015
  • Champion Mastery system fully implemented on all other servers.
V5.6
  • Champion Mastery system fully implemented on the Brazilian server.

References

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