Boomer is a symptom combo exclusive to the Necroa Virus DLC which allows zombies to explode when excited. Severity increases when this combo is in play. The symptom Autothysis and the ability Liquefactive Necrosis are required. The achievement Boomer is earned for forming the combo.
It may based off of a type of zombie from Valve's Left 4 Dead franchise thats explodes when player kills and vomit biles to attract zombies to attack them.
|Symptom Combos in Plague Inc. and Plague Inc: Evolved.|
|Assassin ▪ Bath Time ▪ Blind Genius ▪ Blood in the Air ▪ Boomer ▪ Carpe Jugulum ▪ Cranial Dispersion ▪ Discovery Channel ▪ Fly Magnet ▪ On The Naughty List ▪ Oops ▪ Profuse Bleeding ▪ Projectile Vomiting ▪ Public Defecation ▪ Red Ape Redemption ▪ Red Rain ▪ Rude Awakening ▪ Runner ▪ Spitter ▪ Swine Flu ▪ Tank ▪ Ultimate Christmas ▪ Vampire Bat ▪ Walking Contradiction ▪ Walking Dead ▪ Zombie Panic|