Heavy Flamer, Variant (5e Equipment)
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Martial Ranged Weapons
Despite being developed ahead of its time, flamers are nonetheless popular weaponry among beast hunters, crypt delvers, dungeon divers, and clergymen alike.
Flamers as a weapon class consume oil for ammunition; The heavy flamer consumes 1 pint of oil every time you attack with it. Its storage tank, mounted on the back and connected to the nozzle by a hose, can hold up to 2 gallons of oil (16 pints).
Flame Weapon. When you attack with the heavy flamer, make a weapon attack against all creatures in a straight line within range, dealing the weapon's damage to every creature it hits.