Mechanic

Ignite

Ignite is a damaging Elemental Ailment that deals Fire damage over time for four seconds by default. A Hit's chance to Ignite comes from the target's total Flammability, including Flammability applied by that same Hit.
0.5.4d
Current data

Catalog version 0.5.4d

No direct 0.5 patch change is linked to this page. The displayed values are current for catalog version 0.5.4d.

What Ignite does

Current rules

A Fire Hit first applies Flammability based on its pre-mitigation Fire damage relative to the target's Ailment Threshold, then that Hit rolls its Ignite chance using the new total. A successful Ignite deals base Fire damage per second equal to 20% of the qualifying Fire damage for four seconds. Several Ignites can exist, but only the strongest normally deals damage.

Flammability supplies Ignite chance
Fire Damage no longer has an inherent Ignite chance. A Fire Hit applies Flammability, and the target's total Flammability Magnitude is the chance for a qualifying Hit to Ignite, up to 100%.
The same Hit uses its new Flammability
A Hit applies its Flammability before checking whether that Hit Ignites. Base Flammability is 1% Ignite chance for every 5% of the target's Ailment Threshold dealt as pre-mitigation Fire damage, so the first sufficiently large Fire Hit can Ignite.
Flammability stacks independently
Flammability instances add their Magnitudes together to a maximum of 100% Ignite chance and keep independent durations. The default duration is eight seconds on monsters and four seconds on players.
Base damage is 20% per second
The base Ignite Magnitude is Fire damage per second equal to 20% of the qualifying pre-mitigation Fire damage of the Hit. The default four-second duration therefore deals 80% of that contributing damage before Ignite Magnitude, duration, damage speed, and target mitigation are applied.
Only the strongest Ignite deals damage
Multiple Ignites can remain on one target with independent durations, but they do not normally add their damage together. Only the highest-damage active Ignite deals damage, and the next strongest can take over when it expires.
Resistance is applied separately
The target's Fire Resistance does not reduce the source Hit before Ignite Magnitude is formed and then reduce the Ignite a second time. The Hit and the resulting Fire damage over time are separate damage events and are each mitigated on their own.
Penetration does not affect Ignite
Fire Penetration is restricted to Hits and does not lower Fire Resistance for the separate Ignite damage over time. Exposure changes the target's actual Resistance and can affect both the Fire Hit and the Ignite.
Non-Hit sources need 50% Flammability
Effects that Ignite as though they Hit, including Ignited Ground and some aura-like skills, also apply Flammability but do not make a random Ignite roll. They begin Igniting only after the target reaches at least 50% total Flammability.
Aura Ignites use standard duration
Since patch 0.4.0, Igniting aura effects no longer apply infinite-duration Ignites. They apply regular Ignites with standard duration and can reapply after expiry when the aura next applies Flammability.
Burning is broader than Ignite
Burning means taking Fire damage over time. Ignite causes Burning, but a source of Fire damage over time is not automatically an Ignite and does not automatically use Ignite Magnitude, Flammability, spreading, consumption, or immunity rules.

Applying, scaling, and using Ignite

10 cases
01
Ignite chance supports

Ignite I, Ignite II, and Ignite III make supported Hits more likely to Ignite by improving their Flammability interaction. The later support also makes inflicted Ignites deal damage more quickly.

Related: Ignite I, Ignite II, Ignite III
02
Ignite as though Hitting

Flame Wall, Solar Orb, Volatile Dead, and Radiant Grief Ignite using stated source damage rather than an ordinary Fire Hit. These effects still follow the 50% Flammability rule for non-Hit Igniting effects.

Related: Flame Wall, Solar Orb, Volatile Dead, Radiant Grief, Ignited Ground
03
Compounding Ignite

Incinerate and Flame Breath can Compound Ignites created by one use of the skill. When that use Ignites a target already Ignited by the same use, the old Ignite is removed and the new Ignite gains the skill's compounding multiplier. This is an explicit skill rule, not normal Ignite stacking.

Related: Incinerate, Flame Breath
04
Spread and area payoff

Wildfire spreads supported Ignites after a delay. Phantasmal Arrow applies Ignite around an enemy Ignited by its explosion, while Fan The Flames triggers a fiery cone when supported Wind Skills Hit an Ignited enemy.

Related: Wildfire, Phantasmal Arrow, Fan The Flames
05
Ignite payoff skills

Explosive Concoction throws additional smaller flasks at nearby Ignited enemies. Immolate grants supported Attacks extra Fire damage against Ignited enemies but prevents those Attacks from Igniting by themselves.

Related: Explosive Concoction, Immolate
06
Trigger Energy

Cast on Ignite gains Energy when you Ignite enemies and triggers its socketed Spells at maximum Energy. The Ignite event is the Energy source; the triggered Spell follows the normal restrictions for Meta skills and Triggered skills.

Related: Cast on Ignite, Energy, Trigger
07
Damage type exceptions

Blackflame makes your Ignite deal Chaos damage instead of Fire and changes its duration and Magnitude. The Three Dragons makes Cold Hit damage contribute to Flammability and Ignite instead of Fire Hit damage. Xoph's Pyre lets Chaos damage contribute to Ignites from supported skills.

Related: Blackflame, The Three Dragons, Xoph's Pyre, Contributes
08
Ignite damage supports

Eternal Flame trades Ignite frequency for longer duration. Scouring Flame raises Ignite damage with a Runic Ward cost, Stormfire adds a Lightning damage interaction against Shocked enemies, and Wildfire changes delivery through delayed spread.

Related: Eternal Flame I, Scouring Flame, Stormfire, Wildfire, Runic Ward, Shock
10
Ignite modifiers

Relevant modifiers separately change Flammability Magnitude, Ignite Magnitude, duration, damage speed, avoidance, or the duration and Magnitude of Ignite on you. Flammability chance and Ignite damage are not interchangeable stats.

Related: Search Ignite modifiers

Rare monster modifiers

1 linked

Limits and exceptions

9 rules
  • Fire Damage has no inherent Ignite chance. The target's current Flammability supplies that chance.
  • Flammability applied by a Hit is included in that same Hit's Ignite roll.
  • Flammability Magnitude changes Ignite chance, not Ignite damage. Ignite Magnitude is a separate stat.
  • Only the strongest active Ignite normally deals damage, even when several Ignites remain on the target.
  • Generic damage modifiers are not applied a second time after Ignite Magnitude is calculated from the Hit.
  • Fire Penetration applies to Hits and does not directly increase the separate Ignite damage over time.
  • Burning Fire damage over time is not always Ignite and does not automatically follow Ignite-specific rules.
  • Non-Hit effects that Ignite as though they Hit require at least 50% total Flammability before they Ignite.
  • Compounding is an explicit skill property and must not be treated as the default Ignite stacking rule.