Heavy Stuns occur when a target's Stun bar is filled, interrupts the target's current action and prevent them from taking actions for a few seconds. Hits cause Heavy Stun buildup based on the damage dealt. Players and their Minions usually cannot be Heavily Stunned, but players can receive Heavy Stun buildup where specifically mentioned while taking specific actions (such as raising their Shield, Parrying with a Buckler, or riding a mount).

While an enemy is Heavy Stunned, they cannot act and count as Immobilised. It will also be harder to Heavy Stun them again for a short time afterwards.

Physical damage, and player (but not monster) Melee Damage, each cause 50% more Heavy Stun buildup. For players, these bonuses are multiplicative with each other.

Certain skills and effects allow damage to build up Pinned. Once this build up passes the enemy's Pinned Threshold, they are Pinned, preventing them moving, being moved or Evading for 3 seconds. They are also Light Stunned when they become Pinned.

Pinned targets count as Immobilised.

Totems you place which grant Embankment Auras give a different Aura Buff to Players in range depending on the kind of Totem, as follows:

Artillery Ballista grants 40% increased Immobilisation Buildup.

Siege Ballista grants 50% increased Damage against Immobilised Enemies.

Mortar Cannon grants 15% of Damage Gained as extra Fire.

Shockwave Totem grants 30% increased Area of Effect.

Ancestral Warrior Totem grants 40% increased Glory Generation.

Dark Effigy grants 40% increased Damage over Time.