Silent but Deadly

Silent but Deadly
Info	People are complaining about an awful smell that appears to suddenly appear out of nowhere!
Traits Needed	Corrupted Air Night Wraith Dark Infiltration
Achievement	Silent but Deadly

Dark Night is a symptom combo exclusive to the Shadow Plague DLC. The player can get this combo by evolving Corrupted Air, Night Wraith and Dark Infiltration.

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