GB Bug

GB Bug is an unlockable passive item added in The Binding of Isaac: Afterbirth.

Effects

 * Spawns a familiar that bounces diagonally around the room, deals 8 damage per tick or 120 damage per second and applies a random status effect to enemies it comes in contact with. The familiar also has a chance to re-roll pickups that it passes over into other pickups, chests, or items, in an uncleared room only (with at least one enemy alive).
 * Spawns a familiar that follows Isaac. Double tapping the fire button launches it forward, causing it to reroll the first monster, trinket, or pickup it hits. It respawns after clearing a room.
 * If it cannot reroll an enemy (e.g. a boss), it will deal some damage instead.
 * It can also be used to reroll trinkets into pickups.

Trivia

 * Before Repentance, GB Bug's pickup quote was "Game breaking bug, right away!"
 * This item's in-game appearance may be a reference to "Missingno.", a famous bug occurring in the first Pokémon games.
 * As Edmund confirmed on Twitter the pickup quote "Game breaking bug, right away!" is a reference to a quote by Phil Fish in Indie Game: The Movie, where he says the same words when a bug is discovered in the game "FEZ" on the first day it is being shown at PAX.

Seeds
9B7E 3G67 (Treasure Room adjacent to spawn, curse of the labyrinth) GZWT H4LE (First floor Treasure Room) 44W2 XHJ8 (Treasure Room adjacent to spawn) OCML SLQN (First floor Treasure Room)