Standard 12 gauge 3″ shotgun shells are equipped with a highly explosive warhead. Explosive shotgun shells are Hardmode ammunition used exclusively by the Hydra. They can be purchased from the arms dealer if the Hydra is in the player's inventory. Shoot, variously, an artillery shell, a cartridge case or a shotgun cartridge.
The artillery shell was in use in the 15th century, at first as a simple container for metal or stone pellets, which was scattered by the explosion of the container after it came out of the gun. Explosive shells came into use in the 16th century or perhaps even earlier. They were hollow cast-iron balls filled with gunpowder called bombs. A rudimentary wick was used, consisting of a short tube, filled with slow-burning gunpowder, inserted into a hole through the wall of the bomb.
Until the 18th century, these shells were only used in wide-angle fire (for example, in the 19th century, shells were adopted for direct fire artillery, especially in the form of shrapnel (q, v. D). The dragon's breath shotgun projectile means any shotgun cartridge that contains exothermic pyrophoric metal as a projectile and is designed for the sole purpose of launching or throwing a flame or fireball to simulate a flamethrower.