Heavy Stun | PoE2 Mechanic

What Heavy Stun does

Current rules

Non-Cold damage from Hits builds Heavy Stun on enemies. Player Physical damage and Melee damage each cause 50% more buildup, multiplying to 125% more for a Physical Melee Hit. A Heavy Stunned enemy cannot act, counts as Immobilised and becomes harder to Heavy Stun again for a short time. Players and their Minions normally cannot be Heavy Stunned unless a mechanic explicitly allows buildup.

Non-Cold Hit damage adds buildup: Eligible non-Cold damage from a Hit adds Heavy Stun buildup based on the damage dealt. Cold damage contributes to Chill and Freeze instead of Heavy Stun buildup.
Filling the bar causes Heavy Stun: When buildup reaches the target's Heavy Stun Threshold, the target's current action is interrupted and it cannot act during its Heavy Stun animation.
Physical and player Melee damage have separate multipliers: Player Physical damage and player Melee damage each cause 50% more Heavy Stun buildup. A Physical Melee Hit applies both multipliers for 125% more buildup than a Hit with neither property.
Primed for Stun starts before the bar is full: Normal enemies become Primed at 40% buildup, Magic at 50%, Rare at 60% and Unique at 70%. Primed is an eligibility state for Crushing Blows and named skills, not a Heavy Stun by itself.
Crushing Blows consume the opportunity: A Crushing Blow immediately causes a Heavy Stun when it Hits an enemy that is Primed for Stun. Boneshatter has its own Primed interaction and cannot build Stun with its initial Strike.
Heavy Stunned enemies count as Immobilised: An enemy is unable to act and counts as Immobilised while Heavy Stunned. Effects against Immobilised or Heavy Stunned enemies can therefore apply during that window when their other conditions match.
Buildup decays and repeated Heavy Stuns become harder: Heavy Stun buildup begins to decrease after no new buildup has been applied for a period. After a Heavy Stun ends, the buildup empties and the target is temporarily harder to Heavy Stun again.
Players require an explicit exposure: Players can accumulate Heavy Stun buildup during named states such as active Block, Parry, riding a mount or being Hit while sprinting. A player Heavy Stun lasts 3 seconds and prevents Block and Evasion.

Heavy Stun buildup and payoff states

8 cases

01

Player Physical Melee Hit

Causes 125% more Heavy Stun buildup because the two separate 50% more multipliers apply multiplicatively.

Related: Physical, Melee, Hit

02

Cold Hit

Does not add Heavy Stun buildup from its Cold damage. It contributes to Chill and Freeze instead.

Related: Cold, Chill, Freeze

03

Dazed enemy

Takes 50% more Stun Buildup while Daze lasts. The current base Daze duration is 8 seconds.

Related: Dazes

04

Enemy is Primed for Stun

Has crossed its rarity-specific threshold and can be immediately Heavy Stunned by Crushing Blows or eligible named skills.

Related: Boneshatter

05

Enemy is Heavy Stunned

Cannot act, counts as Immobilised and can enable damage or utility effects that explicitly require Heavy Stun.

Related: Immobilised, Seismic Cry

06

Buildup is not refreshed

Begins decaying after its delay. Continuing to land eligible Hits prevents ordinary decay until the bar fills or application stops.

Related: Hit

07

Player actively Blocks or Parries

Can accumulate Heavy Stun buildup under those skills' rules. Reaching full buildup disables Block and Evasion for 3 seconds.

Related: Block, Raise Shield, Parry, Evasion

08

Increased Stun Buildup

Scales the buildup created by eligible Hits. It does not directly reduce the target's stored Stun Threshold.

Currency: Stone Rune, Greater Stone Rune, Perfect Stone RuneRelated: Stun Threshold

Limits and exceptions

7 rules

Cold damage does not build Heavy Stun.
Primed for Stun is not the same as being Heavy Stunned.
A Crushing Blow needs a Primed enemy unless its own wording states another rule.
Player and Minion Heavy Stun requires an explicit mechanic that allows buildup.
Heavy Stun duration varies by monster and is not universally 3 seconds.
A Heavy Stunned enemy becomes harder to Heavy Stun again for a short time afterward.
Stun Buildup and reduced enemy Stun Threshold are separate modifiers.

Related pages

21 connections

mechanicStun

Stun interrupts the target's current action and briefly prevents it from acting. Path of Exile 2 has two related systems: Light Stun is rolled from the damage of one Hit, while Heavy Stun is caused by filling a separate buildup bar.

mechanicStun Threshold

Stun Threshold is the target-side reference used to determine Light Stun chance and Heavy Stun buildup. Raising your own threshold makes incoming Stuns less likely, while lowering an enemy's threshold makes that enemy easier to Stun.

mechanicStun Recovery

Stun Recovery shortens the time you are unable to act after being Stunned. It does not reduce the chance of a Light Stun, raise Stun Threshold, prevent a Stun, or make Heavy Stun buildup empty faster.

mechanicHit

A Hit is an instantaneous damage event. Any damage that is not damage over time is Hit damage, whether it comes from an Attack, a Spell, Thorns, or another effect.

mechanicPhysical

Physical damage is one of the five Damage Types. It is the most common and the only one reduced by Armour, rather than by a Resistance.

mechanicMelee

Melee Attacks directly hit with a Strike or deal Melee damage through a Slam. They usually scale from a Martial Weapon or Unarmed base, but Melee is not a damage type and does not include Projectiles created by the Attack.

mechanicCold

Cold Damage is one of the five damage types. Cold Hits can Chill and build Freeze, but Chill Magnitude, Freeze Buildup, and Freeze Duration are separate values, and Cold damage from Hits cannot build Heavy Stun.

mechanicChill

Chill is a non-damaging Elemental Ailment that slows action speed. Cold Hits can Chill without a separate application chance, but a calculated Chill below 30% Magnitude is discarded.

mechanicFreeze

Freeze is a non-damaging Cold Ailment that prevents a target from moving or acting. Cold Hits can Freeze directly or add Freeze Buildup, and reaching 100% Buildup makes the target Frozen.

mechanicImmobilised

A target is Immobilised when it cannot move between locations. Pin, Freeze, Heavy Stun, and Electrocution are common ways to cause this state.

mechanicDazes

Daze is an 8-second debuff that makes the affected target take 50% more Stun Buildup. It does not interrupt the target by itself; it prepares the target for faster Heavy Stuns and enables effects that require a Dazed enemy.

mechanicBlock

Block prevents the damage of a blockable Hit. Passive Block rolls the character's Block chance for each eligible Hit, while active Block from a raised shield guarantees a block from the protected direction under that skill's rules.

skillRaise Shield

Raise your Shield to Block all incoming Blockable hits. Release immediately after Blocking when an enemy is close to perform a Shield Bash, damaging and Stunning enemies. While your Shield is raised you cannot be Light Stunned by hits you Block, but Blocking too much damage may Heavy Stun you. You cannot Evade while your Shield is raised, but Evasion instead grants an equal chance to avoid this Heavy Stun buildup.

mechanicParry

Parry is the active Block skill granted by Bucklers. Hold it while facing an enemy to block an eligible Hit, retaliate with a Physical sweep, and apply the Parried debuff.

mechanicEvasion

Evasion Rating grants an entropy-based chance to Evade enemy Hits completely. The actual chance compares the defender's Evasion Rating with the Accuracy Rating of the attacker.

skillBoneshatter

Attack enemies with a melee Strike. The Strike will cause a Heavy Stun on enemies that are Primed for Stun. Upon causing a Heavy Stun it will also create a Shockwave, dealing a large amount of damage in an area.

skillSeismic Cry

Perform a damaging Warcry, Knocking Back nearby enemies and Heavy Stunning enemies that are Primed for Stun. If an enemy is Heavy Stunned or a currently Heavy Stunned enemy is Hit, this Skill Empowers subsequent Slams to perform an additional Aftershock. This Skill's cooldown can be bypassed by expending an Endurance Charge.