Use your favourite features in-game with our Desktop AppBlock is a defensive mechanic in Path of Exile 2. You'll typically find Block related stats on Shields and on the bottom and left sides of the Passive Skill Tree.
Tip: check out our guides on the standard Defence stats in Path of Exile 2: Armour, Energy Shield, Evasion!
Block is a mechanic that fully prevents the Damage of an incoming Hit. All non-Boss Hits can be Blocked by default, however some abilities that are used by bosses will be preceded by an animation in the form of a red flash and an audio cue to signal that they cannot be Blocked or Evaded.
Note: Damage over time does not Hit and therefore cannot be Blocked.
However, unlike Evasion, a Hit that's Blocked has still passed through the Damage calculation. This is an important distinction, as Blocked Damage is still able to inflict on-Hit effects such as Stun or Freeze Buildup based on the Damage that was prevented.
Note: you cannot Block while Frozen or Stunned.
If a Blocked Hit would have caused a Stun, a Blocking animation is played. Modifiers that grant 'increased Block Recovery', such as the one on 
Shield Expertise, shorten the Duration of this animation. A Blocked Hit that wouldn't have caused a Stun does not play a Blocking animation.
Note: a Blocking animation is never played if an entity is Immune to Stun.
The chance to Block a Hit is based on the type of Block. Passive Block is a chance-based system, whilst Active Block is guaranteed under specific conditions, usually provided by an ability.
Note: a Blocked Hit still counts as a Hit for the purpose of on-Hit or when-Hit mechanics.
The most common type of Block is Passive Block, a chance-based stat that's rolled on a per-Hit basis. Unlike Evasion, Passive Block is entirely random, and upon rolling successfully, an incoming Strike or Projectile will have all of its Damage prevented. When Passive Block chance is rolled unsuccessfully, the Hit is not Blocked, and no Damage is prevented.
The base chance to Block is typically derived from an equipped Shield, but can also come from other items such as the 
Barrier Quarterstaff. For example 
Mahuxotl's Machination has a base Block chance of 25%.
When a Shield has an 'increased Block chance' modifier present, this a local modifier that directly scales the base Block chance provided by the Shield. For example 
The Surrender with a modifier roll of '50% increased Block chance' would bring the base Block provided by this Shield from 26% up to 39% (26 * 1.5)
You can also find rarer modifiers that add directly to the base Block chance, such as the one on 
Legionstride. These modifiers are recognisable from their terminology, adding to Block chance rather than increasing it.
Global modifiers that provide 'increased Block chance' do not add their percentage to the base chance obtained from Shields or elsewhere. Instead, these modifiers are multipliers to the base Block chance. Taking the example from above, The Surrender providing 39% base Block chance would be improved to 44% if the player allocated the 
Vigilance Passive Skill Tree Notable (39 * 1.12).
The default maximum Block chance is 50%. This can be improved by rare modifiers such as the one on 
The Anvil. Additionally, the Warbringer's 
Turtle Charm will set your maximum Block chance to 75% but make you take 30% of the Damage from incoming Blocked Hits.
Maximum Block chance is hard-capped at 90%.
Active Block is a term that refers to the innate Block provided by some strength-aligned Shield Skills. When the player's Shield is raised by one such Skill, they will Block any non-Boss Hits that come from the direction they are facing in. Examples of Skills that raise the player's Shield:
Raise Shield
Shield Charge
Resonating Shield
Parry is a defensive Skill that's granted by Buckler Shields. Parry performs a similar Active Block function, but only Blocks a single incoming Blockable Hit per Parry. Check out our full guide on the Parry mechanic here.
When Blocking incoming Hits with Active Block or Parry, the player will build up a Heavy Stun bar based on the amount of Damage prevented. If the Heavy Stun bar reaches full, the player will immediately cease Active Block or Parry and be Heavily Stunned for a 3 second Duration by default. The Heavy Stun bar will naturally empty while the Shield is not raised, and the speed at which this occurs can be improved with modifiers such as the one on the 
Defender's Resolve Passive Skill Tree Notable.
The Heavy Stun bar shown in game on the left side of the UI
Note: Active Block, Parry and Passive Block otherwise share all related mechanics, and Passive Block is still functional during Active Block or Parry.
You can obtain modifiers that will Recover a resource whenever you Block a Hit. For example The Surrender will recover 4% of your maximum Life, whilst the Defensive Reflexes Passive Skill Tree Notable will recover 5 Mana.
The Unique Shield 
Svalinn grants the modifier 'Block chance is Lucky'. This modifier causes Passive Block chance to be rolled twice, choosing the favourable outcome.
Alkem Eira makes the Damage from any incoming Blocked Hits be Recouped as Mana. As Block is calculated post-mitigation, this modifier is more effective if you have weaker defences against the Damage of the Hit because the amount Recouped is based on how much Damage would have been taken if the Hit wasn't Blocked.
