Hercules Beetle

Type	AccessoryCrafting material
Tooltip	Increases summon damage by 15%; Increases the knockback of your minions
Rarity
Buy	40 GC
Sell	8 GC
Research	1 required

The Hercules Beetle is a Hardmode, post-Plantera accessory that increases the damage of summon weapons by 15% and increases their knockback by 2.^[1] The Hercules Beetle can be purchased from the Witch Doctor for 40 GC if he is spoken to in the Jungle after Plantera has been defeated.

Crafting

Result	Ingredients	Crafting station
Papyrus Scarab	Necromantic Scroll Hercules Beetle	Tinkerer's Workshop

Despite the tooltip implying that the accessory boosts knockback of minions only, it also affects sentries and whips(Desktop, Console and Mobile versions).

The Hercules beetle is a real-life insect native to rainforests in Mexico, Central America, South America, and the Lesser Antilles. It is the largest species of rhinoceros beetle and one of the overall largest beetles in the world.
As the item grants 15% increased summon damage and increased summon knockback, it can be considered an upgrade to the Summoner Emblem.