Starcraft t2 Firestorm Flamethrower (5e Equipment)
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Martial Ranged Weapons
A device consisting used to burn your foes that uses napalm. A creature which takes damage from a flamethrower takes 1d6 fire damage at the start of each of its turns, not stacking with itself. A creature can end this damage by using its action to extinguish the flames.
Special. You can make a normal single-target attack with a flamethrower, or you can spray everything in a 20 foot cone in front of you by dispensing the flamethrower's entire payload of 4 shots. Each creature in the area must succeed on a DC 15 Dexterity saving throw to take half of the the flamethrower's normal damage.