From Brotato Wiki
Some Ranged Weapons have Piercing, allowing their projectiles to pierce through, and hit more than one target. However, weapons have a default 50% damage falloff on the projectile for each time it pierces. Each Pumpkin you have reduces this falloff by 15%. So if you have a pumpkin, only 35% damage is lost on each pierce.
- Pumpkins can be stacked, removing 15% each. If you have 4 pumpkins, for a total of 60% reduced damage, the 50% damage falloff is completely removed, and the attacks will deal full damage on each piercing/hit.
- Some some weapons have innate piercing, and come with a different damage falloff. Double Barrel Shotgun only loses 30% Damage per Pierce, so it only needs 2 Pumpkins for full damage. Shredder has a default damage falloff of 0%, meaning it won't need any Pumpkins
- The Damage falloff modification done by Pumpkin is affected by the All Damage Modification changes that characters such as Entrepreneur, who only gains 7.5% Less Damage falloff from a pumpkin (Due to 50% less damage modifications), or One Armed, who gains a whole 30% Damage falloff per Pumpkin. (+100% damage modifications).
- See Piercing for more info and examples.