Health regeneration

Health Regeneration (also known as Hp5 or health per 5 seconds) is a statistic that determines the amount of health that a champion regenerates over a five second period. Each champion starts with a different rate of base health regeneration. This statistic scales additively; meaning that each bonus point acquired directly affects the statistic and is not affected by diminishing returns.

Champion abilities

 * regenerates 0.3 % of his max health each second.
 * causes him to regenerate 40 / 55 / 70 % of his max health over 12 seconds.
 * allows him to regenerate 0.5 % of his maximum health per second after not taking damage for 7 seconds.
 * increases the health regeneration per 5 seconds of nearby turrets and champions by 10 / 15 / 20 / 25.
 * increases his health regeneration per 5 seconds by 35 / 50 / 65 for 25 seconds.
 * increases his healing and regeneration by 8 %. This buff lasts for 10 seconds and stacks up to 4 times.

Masteries

 * increases your total health and mana regeneration by 2 / 3 / 4 %.
 * increases your champion's health regen per 5 seconds by 0.33 / 0.66 / 1 % of your max mana.

Runes

 * and runes increase health regeneration.

Neutral Buffs

 * The buff gives 3 % of your max health in health regeneration per 5 seconds for 8 minutes.

Regeneration reduction
Certain abilities reduce the effectiveness of regeneration. Such abilities do not stack, though they will refresh the duration. All such abilities halve the effectiveness of healing, health regeneration, life steal, and spell vamp.

Champion abilities that reduce health regeneration

 * , when enhanced with, reduces the healing and regeneration of all targets hit by 50 % for 5 seconds.
 * , while active, reduces the healing and regeneration of all targets she hits by 50% for 3 seconds.
 * reduces the healing and regeneration of the target by 50% for 5 seconds.

Items that reduce health regeneration

 * 's active reduces healing and regeneration of the target by 50% for 8 seconds.

Spells that reduce health regeneration

 * reduces healing and regeneration of the target by 50% for 5 seconds, and deals 50 (+20 x level) true damage over the duration.