On Fire!

On Fire! is a debuff which causes the afflicted NPC or player to lose 4 health per second while not regenerating health. This debuff can be canceled prematurely by jumping into Water, or by pouring a Water Bucket over the player's head. If the player is under the effects of the Obsidian Skin Potion, Lava will not burn them.

Immune NPCs
Bosses: Other:
 * all Underworld NPCs
 * all Skeletral NPCs (That is: all Undead NPCs, except Zombie, Doctor Bones and The Groom.)
 * all Underground Hallow NPCs
 * Eater of Worlds
 * Skeletron
 * Wall of Flesh
 * The Destroyer
 * Skeletron Prime
 * Blazing Wheel
 * Cursed Hammer
 * Dungeon Guardian
 * Meteor Head
 * Mimic
 * Pixie
 * Possessed Armor
 * Wraith
 * Wyvern