Locust of Pestilence is an unlockable trinket in The Binding of Isaac, added in the Afterbirth+ DLC.

Upon entering an unexplored room, spawns a Green Locust that dies upon impact with enemies, dealing 2x Isaac's damage for the impact, and poisons the enemy, dealing Isaac's amount of damage for 2 ticks.

Has a 1% chance of being dropped upon defeating Pestilence.

This page shows the latest information as of the new Repentance+ (Online Co-op) DLC.
To see information about this trinket for the previous Repentance version, check this page instead.

Defeat Satan as Apollyon.

The following special synergies and interactions for Locust of Pestilence have been documented.

* Note that not all possible synergies and interactions are listed here.

Below is the Internal Item Description as shown in-game.
Note that some stat changes are not displayed here. Please see the main description for the full effects.

Locust of Pestilence

• Spawns a poisoning locust upon entering a new combat room
• Golden Trinket (without Mom's Box): Spawns 2 poisoning locusts upon entering a new combat room
• Mom's Box: Spawns 2 poisoning locusts upon entering a new combat room
• Mom's Box + Golden Trinket: Spawns 3 poisoning locusts upon entering a new combat room

• Check out the trinket description on the external Isaac Wiki.