Incendiary

The Incendiary elemental property adds the effect of fire to weapons, grenade mods, shields and some enemies. It is most effective against unshielded, flesh enemies, such as Bruisers and younger Skags. Incendiary weapons bullet burst into flames when they impact. When a fire element triggers, the enemy is lit on fire, dealing damage over time. If the enemy dies due to fire damage, their corpse will burn away. The flames spread from enemy to enemy and the effect will stack. If you light an enemy on fire, and he is near another, the second will light on fire. Afterwards they will repeatadly light each other again and again, stacking the effect.