Exstermoonator

The Exstermoonator is a large, Pre-Hardmode, Expert Mode Only ranged weapon that drops from the Cowthulhu's Treasure bag but only with a 10% chance. This increases to a 20% chance in master mode.

Stats
The Exstermoonator deals a lot of damage and is autoswing, yet it is slightly slow and rare to find. However if you find it, there's almost no reason to get another gun. The Exstermoonator will shoot a triple blast of black-and-white flaming bullets that home on enemies. This inflict the Mooing Flames debuff, that burns the player using cow particles and deals 15 damage every 1.5 seconds. It only lasts 10 seconds however.