Mana regeneration

Mana Regeneration (also known as Mp5) is a statistic that determines the amount of mana that a champion regenerates over a five-second period. Each champion that uses mana starts with a certain base rate of mana regeneration, which increases by a small amount at each level-up. It can be further increased by a variety of items and effects, as detailed below. Mana regeneration scales additively, meaning that each bonus point acquired directly affects the statistic. This is true whether the bonus is a flat value or percentage-based.

Champion abilities

 * increases her mana regeneration by 5% of her maximum mana while stealthed.
 * increases his mana regeneration by for 25 seconds.
 * increases his mana regeneration by 1% per 1% mana he is missing.
 * increases his mana regeneration by 5.

Masteries

 * increases your champion's mana regeneration by.

Runes

 * and runes increase mana regeneration.

Neutral buffs

 * The buff regenerates 25 mana per 5 seconds and  of your max mana per second for  minutes.
 * The buff regenerates 1% of your max mana per 5 seconds for 4 minutes.
 * The Crystal Scar's map-wide buff grants 2% bonus mana regeneration for every 1% of mana missing.
 * The Howling Abyss' map-wide buff seems to grant roughly 170% bonus mana regeneration.
 * The Twisted Treeline's map-wide buff grants bonus mana regeneration for every 1% of mana missing.

Trivia
The greatest mana regeneration currently possible is, achieved by. To reach this amount, she must: This makes a total of mana regeneration, as shown below:
 * Have reached level 18 in the last 7 seconds.
 * Have 4 fully farmed.
 * Have an.
 * Have a fully grown.
 * Be affected by a aura.
 * Have 3 points in the mastery.
 * Have 3 points in the mastery.
 * Have 9 marks and 9 glyphs of.
 * Have 9 seals and 3 quintessences of.
 * Be stealthed thanks to her passive,.
 * Be consuming a Mana Potion.
 * Be affected by the Crystal Scar's Aura (and so, be playing Dominion).
 * Have zero mana left.

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If playing in Summoner's Rift, the maximum mana regeneration is, also achieved by. To achieve this, she must: The math in this case is:
 * Have reached level 18 in the last 7 seconds.
 * Have a fully farmed.
 * Have an.
 * Have 4 fully grown.
 * Be affected by a aura.
 * Have 3 points in the mastery.
 * Have 3 points in the mastery.
 * Have 9 marks, 9 seals, 9 glyphs, and 3 quintessences of.
 * Be stealthed thanks to her passive,.
 * Be consuming a Mana Potion.
 * Have zero mana left.
 * Possess the buff.
 * Possess the buff.

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However, it should be noted that these values will not be maintained for longer than half a second, since the % increases depending on missing mana will decrease. Taking this into account, the highest mana regeneration per half-second is in the Crystal Scar, and  in Summoner's Rift.

List of champions' mana regeneration
Mana regen Manaregeneration Regeneración de maná Régénération de mana Regeneracja many 魔法回复