Firestarter

Your melee attacks and abilities have a chance to viciously brand your target, dealing Fire damage over 6 sec, and grant you, stacking up to 15 times. Damage increased per stack to a maximum.

While above 5 stacks, also deals 50% of its damage to you. At 15 stacks, enemies near your target suffer 10% of the damage dealt split between them. decays every 3 sec while out of combat and fades entirely after 15 sec.