Masteries are one of the two level-dependent aspects of the persistent summoner system.  They do not require IP or RP.

There are three mastery trees: Offense, Defense, and Utility. Mastery points are spent on upgrading your champion's abilities ingame.

You are restricted in which upgrades you can purchase by a hierarchical ordering.  You must first purchase the upper upgrades in a tree before you can purchase lower (and usually more powerful) upgrades.  Some upgrades are specifically linked to an upgrade directly above them - you must 'max out' that upgrade before you can purchase any of the lower one.

The reward for reaching the bottom of a tree is a single very significant upgrade.  Because of the amount you must invest in that tree, you can only 'max' out a single tree for any particular game.

You can freely reallocate masteries between each game.

Click on mastery icon to go to its info page.

List of all Masteries

Offense

Icon	Mastery	Number of ranks	Effect per rank	Requirement	Spell Upgraded
	Deadliness	3	Increases your champion's critical strike chance by 0.66/1.33/2%.	None	None
	Cripple	1	Your exhaust spell also reduces the target's armor and magic resistance by 25 for the duration, and increases the duration by 0.5 seconds. The debuff does not stack with itself.	None	Exhaust
	Plentiful Bounty	1	Your smite skill rewards a bonus 5 gold when used, and reduces its cooldown by 5 seconds.	None	Smite
	Archmage's Savvy	3	Increases your ability power by 0.2/.4/.6 per champion level.	None	None
	Sorcery	4	Reduces the cooldown of your champion's abilities by 0.75/1.5/2.25/3%.	4 points in Offense	None
	Alacrity	4	Increases your champion's attack rate by 1/2/3/4%.	4 points in Offense	None
	Archaic Knowledge	1	Your magical spells penetrate 15% of the target's magic resistance.	8 points in Offense and 4 points in Sorcery	None
	Sunder	3	Your physical attacks ignore 2/4/6 of the target's armor.	8 points in Offense	None
	Offensive Mastery	2	Increases the damage you deal to minions by 2/4.	8 points in Offense	None
	Brute Force	3	Increases your champion's attack damage by 1/2/3.	12 points in Offense	None
	Burning Embers	1	While your ignite spell is on cooldown you gain 10 ap.	8 points in Offense	Ignite
	Lethality	3	Increases your champion's critical strike damage by 3.33/6.66/10%.	16 points in Offense	None
	Improved Rally	1	Your rally spell also increases base magical damage by 20%, and increases the duration by 5 seconds.	16 points in Offense	Rally
	Havoc	1	Increases your base damage, and magic damage by 5%.	20 points in Offense	None

Icon	Mastery	Number of ranks	Effect per rank	Requirement	Spell Upgraded
	Mender's Faith	1	Increases the amount your heal spell restores by 75, and reduces the cooldown by 15 seconds.	None	Heal
	Resistance	3	Increases your champion's magic resistance by 2/4/6.	None	None
	Preservation	1	After casting your revive spell, your maximum health is increased by 400 for 120 seconds, and reduces the cooldown by 30 seconds.	None	Revive
	Hardiness	3	Increases your champion's armor by 2/4/6.	None	None
	Strength of Spirit	3	Increases your champion's health regeneration by 0.1/.2/.3% of your maximum mana.	4 points in Defense	None
	Evasion	4	Increases dodge chance by 0.5/1/1.5/2%.	4 points in Defense	None
	Defensive Mastery	2	Your champion takes 1/2 less damage from minions and monsters.	8 points in Defense	None
	Nimbleness	1	On dodge, increases your movement speed by 10% for 5 seconds.	8 points in Defense and 4 points in Dodge	None
	Harden Skin	3	Blocks 1/1.5/2 physical damage.	8 points in Defense and 3 points in Hardiness	None
	Veteran's Scars	4	Increases your champion's health by 15/30/45/60.	12 points in Defense	None
	Willpower	1	Reduces the recharge time for your cleanse spell by 30 seconds.	12 points in Defense	Cleanse
	Ardor	3	Increases your champion's attack speed and ability power by 0.66/1.33/2%, and an increasing amount summing to an additional 0.66/1.33/2% at level 18.	16 points in Defense	None
	Reinforce	1	Changes your fortify spell into a dual ability. While the cooldown is available for fortify, you deal 9 more damage to minions.	16 points in Defense	Fortify
	Tenacity	1	Decreases all damage dealt to your champion by 4%.	20 points in Defense	None

Icon	Mastery	Number of ranks	Effect per rank	Requirement	Spell Upgraded
	Spatial Accuracy	1	Reduces the delay on your teleport spell by 0.5 seconds, and decreases its cooldown by 5 seconds.	None	Teleport
	Good Hands	3	Reduces the time spent dead by 3.33/6.66/10%.	None	None
	Perseverence	3	Increases your total health and mana regeneration by 2/3/4%.	None	None
	Haste	1	Your ghost spell increases movement speed by an additional 8%, and increases the duration by 1.5 seconds.	None	Ghost
	Awareness	4	Increases the amount of experience your champion gains by 1.25/2.5/3.75/5%.	4 points in Utility	None
	Expanded Mind	4	Increases your champion's mana by 1.25/2.5/3.75/5% of your maximum mana.	4 points in Utility	None
	Greed	1	Generates 1 gold every 10 seconds.	8 points in Utility	None
	Meditation	3	Increases mana regeneration by 0.33/.66/1 per second.	8 points in Utility	None
	Utility Mastery	2	Increases the duration of neutral monster buff by 15/30%.	8 points in Utility	None
	Quickness	3	Increases your base movement speed by 1/2/3%.	12 points in Utility	None
	Blink of an Eye	1	Reduces the cooldown of flash by 15 seconds.	12 points in utility	Flash
	Intelligence	3	Reduces your champion's cooldowns by 2/4/6%.	16 points in Utility	None
	Mystical Vision	1	Your clairvoyance spell lasts an additional 4 seconds, and has a 5 seconds reduced cooldown.	16 points in Utility	Clairvoyance
	Presence of the Master	1	Reduces the recharge time of your summoner spells by 15%.	20 points in Utility	None