This guide explains the Double Herald setup (Herald of Ice + Herald of Thunder) in Path of Exile 2, a technique that creates a chain reaction clearing entire screens with a single hit. While understanding the interaction isn't strictly necessary, it helps with build theorycrafting.
How to Use Double Herald (Herald of Ice + Herald of Thunder) in PoE 2
Four key elements are required:
Herald of Ice Skill Gem socketed with 
Lightning Infusion Support Gem.
Herald of Thunder Skill Gem socketed with 
Cold Infusion Support Gem ( 
Glaciation is recommended).- 60 Spirit.
- A method for inflicting Cold damage.
Remember to activate both Heralds in the skills menu.
Effective ways to initially proc Herald of Ice include:
- Inherent skills like the Monk's Ice Strike.
- Passive skills boosting Freeze buildup.
- Weapons/gloves with flat cold damage.
Against the Darkness Time-Lost Diamond Jewel (+Cold damage%).
How Herald of Ice and Thunder Interact in PoE 2
Herald of Ice activates when an enemy is Shattered (attacking a frozen enemy). Crucially, Herald of Ice's cold damage cannot Freeze, preventing self-sustaining chain reactions.
Herald of Thunder activates upon killing a Shocked enemy. Similarly, it cannot inflict Shock independently.
The synergy lies in the Support Gems: Lightning Infusion on Herald of Ice converts some damage to Lightning (which can Shock), and Cold Infusion on Herald of Thunder converts some damage to Cold (which can Freeze).
Ideally, this creates an infinite loop: Herald of Ice shocks, triggering Herald of Thunder, which freezes, triggering Herald of Ice, and so on. Realistically, the chain usually ends after one or two cycles due to the need for a continuous supply of monsters. Breaches are particularly effective due to their high enemy density.
Initiating the chain requires proccing Herald of Ice first (via Freeze and Shatter, using a cold skill like Ice Strike). This is because Freeze is easier to inflict than Shock, and Herald of Thunder's lightning bolts have better range.
