Magic penetration

 Magic penetration (also referred to as  MPen) is a champion statistic that determines the amount of a target's  magic resistance that will be ignored when the user deals magic damage. Percentage magic penetration and flat magic penetration have no effect if the target's magic resistance is less than or equal to 0.

Magic resistance reduction is an effect that reduces the target's magic resistance for a period of time, by an amount or percentage. Flat magic resistance reduction can reduce the value below 0, while percentage magic resistance reduction cannot.

It is important to note that penetration treats the target's resistances as being multiplied by a percentage or reduced by a flat amount, in contrast to reduction which applies to the target's resistances as a whole.

All champions have 0 base flat magic penetration and percent magic penetration, but they can be increased by items, runes, and with certain champions' passive ability effects.

Order of calculations

Magic penetration and magic resistance reduction are considered in the following order:

1. Magic resistance reduction, flat
2. Magic resistance reduction, percentage
3. Magic penetration, percentage
4. Magic penetration, flat

Flat magic resistance reduction

The target's magic resistance is reduced by an amount. Flat magic resistance reduction stacks additively.

Example: 20 magic resistance reduction reduces the target's magic resistance by 20, so a target with 30 magic resistance will be reduced to 10 magic resistance. (30 − 20 = 10)

Flat magic resistance reduction can reduce a target's magic resistance below zero. For example, if an enemy with 10 magic resistance has their magic resistance reduced by 25, the enemy will have −15 magic resistance.

Percentage magic resistance reduction

The target's magic resistance is multiplied by a percentage (100% − the listed reduction). Percentage magic resistance reduction stacks multiplicatively and is ignored if the target's magic resistance is 0 or less.

Example: 20% magic resistance reduction multiplies the target's magic resistance to 80%, so a target with 30 magic resistance will be reduced to 24 magic resist. (30 × 0.8 = 24)

Percentage magic resistance reduction reduces more magic resistance on targets with higher magic resistance. For instance, with 40% magic resistance reduction, a target with 200 magic resistance will lose 80 while a target with only 50 magic resistance will lose 20.

Percentage magic penetration

The target's magic resistance is treated as being multiplied by a percentage for purposes of damage calculation (100% − the listed penetration). Percentage magic penetration stacks multiplicatively and is ignored if the target's magic resistance is 0 or less.

Example: 20% magic penetration causes the target to take damage as if its magic resistance was multiplied by 80%, so a target with 30 magic resistance will be treated as though it had 24 for purposes of damage calculation (the target's actual magic resistance value will not change, however).

Because the target's actual magic resistance value does not change, anything else depending on that value also doesn't change.

Percentage magic penetration reduces more magic resistance on targets with higher magic resistance. For instance, with 40% magic penetration, a target with 200 magic resistance will be considered as having 80 less while a target with only 50 magic resistance will be considered as having 20 less.

Gold Value ​​

• Percentage magic penetration has a gold value of 46.15 per point.

Flat magic penetration

The target's magic resistance is treated as being reduced by an amount for purposes of damage calculation, but cannot be reduced below 0. Flat magic penetration stacks additively.

Example: 20 magic penetration causes the target to take damage as if its magic resistance was 20 less, so a target with 30 magic resistance will be treated as though it had 10 for purposes of damage calculation (the target's actual magic resistance value will not change, however).

Because the target's actual magic resistance value does not change, anything else depending on that value also doesn't change.

Gold Value ​​

• Flat magic penetration has a gold value of 37.33 per point.

Examples

Given 10 flat magic penetration and 35% magic penetration, and the target is affected by 20 flat magic resistance reduction and 30% magic resistance reduction;

• Target A has 80 magic resistance.
  • The 80 is reduced to 60 by the 20 magic resistance reduction.
  • The 60 is reduced to 42 by the 30% magic resistance reduction.
  • The 42 is considered to be 27.3 by the 35% magic resistance penetration.
  • The 27.3 is considered to be 17.3 by the 10 magic resistance penetration.
  • Target A takes damage as if it has 17.3 magic resistance.
• Target B has 18 magic resistance.
  • The 18 is reduced to −2 by the 20 magic resistance reduction.
  • The −2 is not affected by any further calculations because it is less than 0.
    • Target B takes damage as if it has −2 magic resistance.

Increasing flat magic penetration

Items

This table is automatically generated based on the data from Module:ItemData/data.

Item	Cost	Amount	Availability
Detonation Orb Detonation Orb	0	12	Arena
Flesheater Flesheater	0	18	Arena
Kinkou Jitte Kinkou Jitte	0	12	Arena
Shadowflame Shadowflame	3200	15	Nexus Blitz, Arena, Classic Summoner's Rift 5v5, All Random All Mid
Sorcerer's Shoes Sorcerer's Shoes	1100	12	Nexus Blitz, Arena, Classic Summoner's Rift 5v5, All Random All Mid
Stormsurge Stormsurge	2900	15	Nexus Blitz, Arena, Classic Summoner's Rift 5v5, All Random All Mid
Talisman of Ascension Talisman of Ascension	0	0	Arena

Increasing percent magic penetration

Champion abilities

• Mordekaiser's Death's Grasp

Items

This table is automatically generated based on the data from Module:ItemData/data.

Item	Cost	Amount	Availability
Blighting Jewel Blighting Jewel	1100	13%	Nexus Blitz, Classic Summoner's Rift 5v5, All Random All Mid
Cryptbloom Cryptbloom	2850	30%	Nexus Blitz, Arena, Classic Summoner's Rift 5v5, All Random All Mid
Perplexity Perplexity	2500	30%	Arena
Talisman of Ascension Talisman of Ascension	0	0%	Arena
Void Staff Void Staff	3000	40%	Nexus Blitz, Arena, Classic Summoner's Rift 5v5, All Random All Mid

Item passives

• Terminus

Reducing magic resistance

Champion abilities

Percentage reduction

• Briar's Head Rush
• Evelynn's Allure
• Jayce's Transform Mercury Cannon
• Karthus' Wall of Pain
• Kayle's Radiant Blast
• Kog'Maw's Caustic Spittle
• Mordekaiser's Realm of Death
• Rell's Break the Mold
• Rumble's Electro Harpoon
• Trundle's Subjugate
• Zoe's Sleepy Trouble Bubble

Flat reduction

• Corki's Gatling Gun
• Rell's Break the Mold

Items

Percentage reduction

• Abyssal Mask

Flat reduction

• Malignance

Monsters

Flat reduction

• Baron Nashor's Void Corruption

Notes

• Magic penetration will apply to any and all sources of magic damage.
  • It will apply to the damage dealt to any unit, including turrets.
• Magic resistance reduction will affect the magic damage from any unit source.
• Percentage penetration is applied before flat penetration.

Trivia

Last updated: October 1st, 2024 (V14.19)

Highest Magic Penetration (flat)

The highest amount of flat magic penetration any champion can obtain is 45.

• Items:
  • Sorcerer's Shoes - 15
  • Shadowflame - 15
  • Stormsurge - 15
• Relevant mathematics:
  • Items = 15 + 15 + 15 = 45 flat magic penetration

Highest Magic Penetration (%)

The highest amount of percentage magic penetration any champion can obtain is 40% due to Void Staff.

The highest amount obtainable in the game is 49% with Mordekaiser when he has Void Staff and his Death's Grasp is at rank 5.

• Relevant mathematics:
  • (1 - 0.4) × (1 - 0.15) = 0.51
    • 1 - 0.51 = 0.49 × 100 = 49% magic penetration

Media

Magic resistance reduced indicator

Armor and magic resistance reduced indicator

See also

• Magic resistance
• Armor penetration
• Champion's stats

References

Champion statistics