The Bile Bomb (a.k.a. Boomer Bile, Vomit jar or simply puke) is a new weapon which appears in Left 4 Dead 2. The weapon was first mentioned in the achievement list. The Bile bomb is a throwable glass jar containing the green Boomer bile. When thrown, it sends the Infected horde to wherever it hits, and potentially causing "friendly-fire" by leading the Horde to attack any Infected coated in the bile. Bile bombs, overall, allow for a brief moment of rest and preparation during a battle.