+% Fire Skill Damage applies a percentage increase to any fire skill damage (after any synergy bonus), or integer or percentage fire damage added to any melee attacks of the user (so it applies to the percentages added by Dragon Talon or Vengeance, but it does not apply to physical attack damage converted to fire by Fire Arrow or Fists of Fire).
- When present on two weapons, the percentages of both are summed and applied to skill damage, and attack damage of either weapon when using a melee attack.
- It applies to skill damage applied by missiles when created, and other damage when applied. If there is a delay between skill usage and missile creation (as there can be with Exploding Arrow and Immolation Arrow explosions, Firestorm, Blaze, Fire Wall and Meteor fires, Fissure cracks, and Volcano and Armageddon rocks) or skill usage and damage (as with Enchant and the first two Fists of Fire charges), swapping weapons or other items to apply a higher percentage may result in more damage. 
- It applies to Enchant skill damage when cast and Holy Fire skill damage before it is added to any attack, then again when using a melee attack.
- Character screen displays it being applied to ranged attack damage, but this is not actually the case. 
- It does not apply to a missile's own damage, so it does not apply to Immolation Arrow, Molten Boulder or Armageddon fires (despite what is displayed by skill descriptions), the fires released by the third Fists of Fire charge, or the meteor and fires released by the first Phoenix Strike charge.
- That equipped by the user does not apply to pets summoned by that user, so it does not apply to Fire Golem or Necromages; this includes the sentry traps Wake of Fire and Wake of Inferno, and any fire attack damage of Blade Sentinel, despite what is displayed by the character screen and skill descriptions (with the exception of Wake of Inferno's skill description). 
- It does not apply to Corpse Explosion, Death Sentry corpse explosions or Fire Enchanted explosions.